Add cable management: drawing, cores, numbering, cross-references and cable list

Cables are drawn line objects (toolbar button next to the auto
break/reconnect button, click-move-click, right click cancels), not
components. The type comes from a CSV catalog following the material
list pattern (designation, cores, core colours, editable through the
entry dialog with "Nouvelle entrée" / "Modifier l'entrée").

Each core is bound to the wire its colour label stands on, and the
cable reference is generated per core and written into the Conductor
entry via Conductor::setCableReference(label, cable uuid, slot). The
conductor entry is where it has to live because the terminal strip
plan (Klemmenplan) consumes it in the next step.

Numbering: "Cables" rule under Programmeinstellungen/Neues
Projekt/Nummerierung auto (mirrored in project properties), literal
"W" fallback without a rule, French gate dialog when no rule exists,
Nummerierung menu with the renumber dialog (preferred axis, per-folio
counter, rule and counter state written back, hand-typed names ask,
whole-project scope).

Also included: label block and under-line texts with per-text font and
alignment plus the material-list cell margins, free-core placement and
right-click removal, claim questions for wires of other cables,
multi-selection drag as one undo step, type change with confirmation,
cross-references for type "Cable" (%f-%l%c, own font, clickable links
in exported PDFs), report propagation of the cable definition,
Listes menu (table of contents, material list, terminal strip manager,
terminal generator plugin, cable list), cable list with freely
selectable columns (installation/localisation of cable, start and end,
Blatt start/end, length, used cores...), CSV export dialog with column
pick and preview in the Projekt menu, script API (addTable kind
"cable_list", exportCableList) and a unit test for the type catalog.

sources/autoNum/ui/selectautonumw.h

@@ -27,6 +27,7 @@ class NumPartEditorW;
 class QAbstractButton;
 class FormulaAutonumberingW;
 class QComboBox;
+class QPushButton;
 
 namespace Ui {
 	class SelectAutonumW;
@@ -52,10 +53,54 @@ class SelectAutonumW : public QWidget
 		void contextToFormula ();
 		QString formula();
 		QComboBox *contextComboBox() const;
+		/**
+			Show this editor as the only numbering rule there is: the
+			row which lets several named numberings be kept and chosen
+			between is hidden, so the rule being edited is the one and
+			only. Everything else -- the definition itself, the buttons
+			around it -- stays exactly as it is for the other kinds.
+		*/
+		void setSingleRuleMode(bool single);
+		bool isSingleRuleMode() const { return m_single_rule; }
+		/**
+			True while everything the editor holds is filled in well
+			enough to be a rule -- no variable left with nothing in it.
+			The Apply button says the same thing; this is so that a page
+			which saves on its own way knows it too, rather than writing
+			a rule nobody has finished filling in.
+		*/
+		bool isValid();
+		/**
+			True while the rule on show has been touched since it was
+			read or since it was last applied: a page which saves on
+			its own way (the cable rule does) writes it only when there
+			is something to write, so that confirming a window with
+			nothing changed in it leaves the project alone.
+		*/
+		bool isModified() const { return m_dirty; }
+		/**
+			Show the button which takes the rule itself away, which is
+			the only way to stop numbering cables automatically again:
+			the row the other numberings delete from is hidden here, so
+			a single rule would have no way out at all. The page behind
+			the editor says whether there is a rule to take away at the
+			moment -- without one the button has nothing to do and is
+			kept out of sight.
+			@param can_remove true when a rule is really there
+		*/
+		void setRuleRemovable(bool can_remove);
 
 	signals:
 		void applyPressed();
 		void removeClicked();
+			/**
+				Sent whenever what the rule holds is edited -- a
+				field of a part changed, a part added, a part taken
+				away -- so that a window holding this editor can let
+				its own buttons say whether there is something to
+				write now.
+			*/
+		void contextEdited();
 
 		//SLOT
 	private slots:
@@ -76,7 +121,19 @@ class SelectAutonumW : public QWidget
 		NumerotationContext m_context;
 		FormulaAutonumberingW *m_feaw;
 		FormulaAutonumberingW *m_fcaw;
-		int m_edited_type = -1; ///<0 == element : 1 == conductor : 2 == folio
+		int m_edited_type = -1; ///<0 == element : 1 == conductor : 2 == folio : 3 == cable
+			///< when true, the row of available numberings is hidden and
+			///< this editor holds the one rule there is (see setSingleRuleMode)
+		bool m_single_rule = false;
+			///< true from the moment the rule on show is touched until
+			///< it is read again or applied (see isModified)
+		bool m_dirty = false;
+			///< the button which takes the whole rule away, built for
+			///< the one kind of numbering which has no list to delete
+			///< it from (see setRuleRemovable)
+		QPushButton *m_rule_remove_pb = nullptr;
+			///< whether such a rule is there to be taken away
+		bool m_rule_removable = false;
 };
 
 #endif // SELECTAUTONUMW_H