Replace some remaining non-Unicode string functionality

Only the project files for OSX need to be changed - the others remain
Merge branch 'refactor-syntax_unicode' into refactor-syntax_unicode_text_stream
Add to iOS project file for libfoundation
Update the Linux/Android libfoundation makefiles
Add to VC project file for Win32
Fixes and tweaks to the text filters
Merge branch 'refactor-syntax_unicode' into refactor-syntax_unicode_text_stream
Fix a problem in the stub generator script
Fix an uninitialised variable
Some clean-ups and fixes
[[ Bug 12138 ]] 'drawer ... at <position>' codepath resulted in nil pointer dereference
[[ CombiningChars ]] Fixes the 'for each char/trueword/sentence' command, which was broken with combining chars
Fixes the cursor positionning when combining char are type, within the Script Editor.
Auto-indenting is broken whenever a surrogate pair is present in a script, since FirstIndexOfChar is still offset by 1 for each surrogate pair
[[ CombiningChars ]] Fixes marking of lines/item/word/token when a string contains surrogate pair
Merge branch 'refactor-syntax_unicode' into refactor-syntax_unicode_text_stream
Merge branch 'refactor-syntax_unicode' into refactor-syntax_unicode_text_stream
Update DivideAtChar to use exact comparison where possible; update any string comparisons with empty to use MCStringIsEmpty
[[ Bug 12143 ]] The mousechunk end index is one larger than it ought to be
[[ Bug 12118 ]] revExecuteSQL writes incomplete data into SQLite BLOB columns
[[ Bug 12147 ]] create button in group command fails
[[ Bug 12150 ]]  LiveCode crashes when changing the window kind