When a folio report have a text item witch must display the information
'tension protocol' the text is empty.
Replace the string 'tension/protocol' by 'tension_protocol' in
QETInformation namespace.
Move the static QStrings of the namespace QETInformation from
qetinformation.cpp to qetinformation.h to be use everywhere in the code.
Replace QETApp::diagramInfoKeys() by QETInformation::diagramInfoKeys()
and QETApp::diagramTranslatedInfoKey(str) by
QETInformation::translatedInfoKey(str)
Replace QETApp::conductorInfoKeys() and
QETApp::conductorTranslatedInfoKey(const QString &key) by
QETInformation::conductorInfoKeys() and
QETInformation::translatedInfoKey