[markdown mode] recognize escapes

fixes #1434
add more modes
fix #1326 L|UL|ULL highlighting in c++ numbers
fix #1315 '#' symbol and preprocessor directive can be separated with spaces
add more modes
Merge pull request #1445 from ajaxorg/highlighting/bugfix

Add more modes
fixing emacs multiselect cut/copy/paste
fix exitMultiSelectMode
emacs: add contents of copy/cut editor events to killring
emacs: deactivate mark on kill-ring-save
emacs: adding mark-ring
emacs: exchangePointAndMark uses last mark if selection empty
emacs: use mark ring instead of single mark
emacs: fix copy event handler
emacs: fix handling of universalArgument, it sets data.count to 4
emacs: C-u C-space fix (setMark)
emacs: C-u C-x C-x fix (exchangePointAndMark)
emacs: fix bindKey
register all partial key combos as null commands
to be able to activate key combos with arbitrary length
Example: if keyPart is "C-c C-l t" then "C-c C-l t" will
get command assigned and "C-c" and "C-c C-l" will get
a null command assigned