Implemented parsing for 'start using font file thefile [globally]' and 'stop using font file thefile', implanted Windows functionality (untested), partially implemented OS X (load tested, unload not working yet).
Changed [[ USE FONT ]] to [[ DynamicFonts ]]
Changed loadFontGobally to is_globally and made a 1 bit bitfield.
Removed global for storing fonts in use. started refactoring based on runrevmark suggestions.
Merge remote-tracking branch 'trevordevore/load-font' into feature/load-font

Conflicts:
	engine/src/executionerrors.h
	engine/src/parsedef.h
[[ DynamicFonts ]] refactored to use MCLoadedFont
 - commit also resolves a merge issue from the previous commit
[[ DynamicFonts ]] Fixed some issues on windows. include sys/stat, use ANSI api variants.
[[ DynamicFonts ]] Documentation and some changes for more appropriate error handling
Merge branch 'feature/load-font' of https://github.com/montegoulding/livecode into feature-start_using_font_file

Conflicts:
	engine/src/executionerrors.h
	engine/src/parsedef.h
	engine/src/property.cpp
	revvideograbber/revvideograbber.xcodeproj/project.pbxproj
[[ DynamicFonts ]] Made MCLoadedFont opaque.
[[ DynamicFonts ]] Fixed memory leaks and minor code tweaks.
[[ DynamicFonts ]] Added flushing and remapping of fonts after load / unload of font.
Merge branch 'feature-dynamic_fonts' into develop