Make English the source language of the interface text

Every tr() source string in the code and the forms is now the English
text, and French is a translation (qet_fr.ts) like the other languages.
Generated, not hand-edited: master ef795a21e5 converted by
qet-en-source (harness 4c4ddc9).

3144 messages get an English source, 665 already had one, 0 left French; 8 shared-wording pairs disambiguated.
C++: 2904 literals in 233 files. Forms: 809 strings in 65 files. All 34 .ts files re-keyed; qet_fr.ts filled.
lupdate check: PASS. What each of 38 languages shows, old vs new: same 118266, English instead of French 38433, comment fallback 51, differences 0.

sources/qetproject.cpp

@@ -614,21 +614,21 @@ QString QETProject::pathNameTitle() const
 	if (!project_title_.isEmpty()) {
 		final_title = QString(
 			tr(
-				"Projet « %1 : %2»",
+				"Project « %1 : %2»",
 				"displayed title for a ProjectView - %1 is the project title, -%2 is the project path"
 			)
 		).arg(project_title_, m_file_path);
 	} else if (!m_file_path.isEmpty()) {
 		final_title = QString(
 			tr(
-				"Projet %1",
+				"Project %1",
 				"displayed title for a title-less project - %1 is the file name"
 			)
 		).arg(QFileInfo(m_file_path).completeBaseName());
 	} else {
 		final_title = QString(
 			tr(
-				"Projet sans titre",
+				"Untitled project",
 				"displayed title for a project-less, file-less project"
 			)
 		);
@@ -637,7 +637,7 @@ QString QETProject::pathNameTitle() const
 	if (isReadOnly()) {
 		final_title = QString(
 			tr(
-				"%1 [lecture seule]",
+				"%1 [read-only]",
 				"displayed title for a read-only project - %1 is a displayable title"
 			)
 		).arg(final_title);
@@ -647,7 +647,7 @@ QString QETProject::pathNameTitle() const
 	if (m_modified || !m_undo_stack->isClean()) {
 		final_title = QString(
 			tr(
-				"%1 [modifié]",
+				"%1 [modified]",
 				"displayed title for a modified project - %1 is a displayable title"
 			)
 		).arg(final_title);
@@ -1760,12 +1760,13 @@ ElementsLocation QETProject::importElement(ElementsLocation &location)
 				QDomElement new_kind = location.xml().firstChildElement("kindInformations");
 				if (!new_kind.firstChildElement("slaveContactGroups").isNull()) {
 					QMessageBox::StandardButton answer = QET::QetMessageBox::warning(nullptr,
-						tr("Système de contacts modifié"),
-						tr("Le nouvel élément définit des groupes de contacts esclaves.\n"
-						   "Les éléments esclaves existants ne seront pas automatiquement "
-						   "assignés. Vous devrez relier manuellement les esclaves "
-						   "et assigner les groupes de contacts.\n\n"
-						   "Voulez-vous continuer ?"),
+						tr("Modified contact system"),
+						tr("The new element defines slave contact groups.\n"
+						   "Existing slave elements will not be automatically assigned. "
+						   "You will need to link the slaves manually and assign the "
+						   "contact groups.\n"
+						   "\n"
+						   "Do you wish to continue?"),
 						QMessageBox::Yes | QMessageBox::No,
 						QMessageBox::Yes);
 					if (answer == QMessageBox::No) {
@@ -1849,7 +1850,7 @@ QString QETProject::integrateTitleBlockTemplate(const TitleBlockTemplateLocation
 
 	if (!m_titleblocks_collection.setTemplateXmlDescription(target_name, src_tbt.getTemplateXmlDescription()))
 	{
-		handler -> errorWithATemplate(src_tbt, tr("Une erreur s'est produite durant l'intégration du modèle.", "error message"));
+		handler -> errorWithATemplate(src_tbt, tr("An error occurred during the template integration.", "error message"));
 		target_name = QString();
 	}
 	return(target_name);
@@ -2003,16 +2004,16 @@ void QETProject::readProjectXml(QDomDocument &xml_project)
 			{
 				int ret = QET::QetMessageBox::warning(
 							nullptr,
-							tr("Avertissement",
+							tr("Warning",
 							   "message box title"),
-							tr("Ce document semble avoir été enregistré avec une version %1"
-							   "\n qui est ultérieure à votre version !"
-							   " \n"
-							   "Vous utilisez actuellement QElectroTech en version %2")
+							tr("This document appears to have been saved with version %1\n"
+							   " which is later than your version ! \n"
+							   "You are currently using QElectroTech in version %2")
 							.arg(root_elmt.attribute(QStringLiteral("version")), QetVersion::currentVersion().toString() %
-							tr(".\n Il est alors possible que l'ouverture de tout ou partie de ce "
-							   "document échoue.\n"
-							   "Que désirez vous faire ?"),
+							tr(".\n"
+							   " It is then possible that the opening of all or part of this "
+							   "document fails.\n"
+							   "What do you wish to do ?"),
 							   "message box content"),
 							  QMessageBox::Open | QMessageBox::Cancel
 							  );
@@ -2030,14 +2031,14 @@ void QETProject::readProjectXml(QDomDocument &xml_project)
 			{
 				auto ret = QET::QetMessageBox::warning(
 							nullptr,
-							tr("Avertissement ", "message box title"),
-							tr("Le projet que vous tentez d'ouvrir est partiellement "
-							   "compatible avec votre version %1 de QElectroTech.\n")
+							tr("Warning ", "message box title"),
+							tr("The project you are trying to open is partially "
+							   "compatible with your version %1 of QElectroTech.\n")
 							.arg(QetVersion::currentVersion().toString()) %
-							tr("Afin de le rendre totalement compatible veuillez ouvrir ce même projet "
-							   "avec la version 0.8, ou 0.80 de QElectroTech et sauvegarder le projet "
-							   "et l'ouvrir à  nouveau avec cette version.\n"
-							   "Que désirez vous faire ?"),
+							tr("In order to make it fully compatible please open this same project with "
+							   "version 0.8, or 0.80 of QElectroTech and save the project and open it "
+							   "again with this version.\n"
+							   "What do you wish to do ?"),
 							   QMessageBox::Open | QMessageBox::Cancel
 							  );
 
@@ -2143,10 +2144,8 @@ void QETProject::readDiagramsXml(QDomDocument &xml_project)
 		dlgWaiting = DialogWaiting::instance();
 		dlgWaiting -> setModal(true);
 		dlgWaiting -> show();
-		dlgWaiting -> setTitle(tr("<p align=\"center\">"
-					  "<b>Ouverture du projet en cours...</b><br/>"
-					  "Création des folios"
-					  "</p>"));
+		dlgWaiting -> setTitle(tr("<p align=\"center\"><b>Opening the project "
+					  "...</b><br/>Creation of sheets</p>"));
 	}
 
 	//Search the diagrams in the project
@@ -2197,10 +2196,8 @@ void QETProject::readDiagramsXml(QDomDocument &xml_project)
 		//and refresh the text of conductor
 	if(dlgWaiting)
 	{
-		dlgWaiting->setTitle( tr("<p align=\"center\">"
-								 "<b>Ouverture du projet en cours...</b><br/>"
-								 "Mise en place des références croisées"
-								 "</p>"));
+		dlgWaiting->setTitle( tr("<p align=\"center\"><b>Opening the project "
+								 "...</b><br/>Setting up cross references</p>"));
 	}
 }