Support for \slash and \nobreakdash-

Support for \slash and \nobreakdash-

* src/lfuns.h:
* src/Text3.cpp:
* src/insets/InsetMathNest.cpp:
* src/insets/insetCollapsable:
	- new LFUN_SPECIALCHAR_INSERT
	- nuke LFUN_HYPHENATION_POINT_INSERT,
	  LFUN_LIGATURE_BREAK_INSERT,
	  LFUN_DOTS_INSERT,
               LFUN_END_OF_SENTENCE_PERIOD_INSERT,
	  LFUN_MENU_SEPARATOR_INSERT
	  (functions now handled as arguments of the above)

* src/insets/InsetSpecialChar.{cpp,h}:
	- implement \slash and \nobreakdash-

* src/Buffer.cpp:
	- increment format to 307.
* lib/lyx2lyx/LyX.py:
* lib/lyx2lyx/lyx_1_6.py:
	- reversion methods for SpecialChar \slash{} and
	  SpecialChar \nobreakdash-
* development/FORMAT:
	- document file format change

* lib/ui/stdmenus.inc:
* lib/ui/classic.ui:
	- add new SpecialChars to the menus, adapt lfuns to new scheme

* lib/bind/aqua.bind:
* lib/bind/cua.bind:
* lib/bind/emacs.bind:
* lib/bind/fi/menus.bind:
* lib/bind/mac.bind:
* lib/bind/menus.bind:
* lib/bind/sciword.bind:
* lib/bind/xemacs.bind:
	- add shortcuts for new SpecialChars, adapt lfuns to new scheme

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@21989 a592a061-630c-0410-9148-cb99ea01b6c8