updating the description to current status

Missing shortcuts in menus
=>
in menus, Ampersand no shown in keyboard shortcuts

Revision 8142 skips Qt's shortcuts and routes all keypresses through the editor. This ensures consistent shortcuts (and might avoid "Ambiguous shortcut" warnings).

However, the issue with the ampersand in the menus is unresolved: Qt refuses to display one if using QKeySequence, even when escaped as the docs suggest.

Unresolved as well is the issue with the menu Insert->Mathematics.

The reason some shortcuts do work but Alt-+ under MacOS doesn't is that this key combination means ± in this OS, which TeXmacs correctly interprets as the <pm> ("plus minus") sign. IF the View menu has been displayed, a QKeySequence has been installed for Alt-+ and the QTMWidget never sees the keypress.

Under MacOS, using Alt+ for shortcuts may lead to many such problems, since many characters are typed with alt. This is my whole keyboard with Alt pressed (notice that some are actually indispensable):
„¡“¶¢[]|{}≠¿'«∑€®†Ω¨⁄øπ•±å‚∂ƒ©ªº∆@œæ‘¥≈ç√∫~µ∞…–

Because menus are implemented with promise widgets, they are not actually instantiated until shown. This means that the Qt Shortcuts aren't created and attached to a widget until they must be displayed. I don't know how to overcome this without forcing the instantiation of the promise widget. The solution is therefore:

1. Don't use Alt-anything under MacOS.
2. Stop using QKeySequences and let the event handler in the QTMWidget handle all keypresses. This makes more sense since most menu items should only be active while the focus is in a texmacs widget.
3. Don't use QKeyEvent::text() in QTMWidget::keyPressEvent(), since this translates the key combination into Unicode (with caps, and  stuff like Alt-+ -> ±, etc)

The same problem occurs under MacOS.