init src.
移植xCairo，基于xC和XClib
cairo base on xC and xClib.
INT_MAX/MIN modify to XINT32_MAX/MIN.
Merge pull request #2 from tangbo2013/first_pullrequest

init src.
rm all unused .c files and make/check files.
remove unused header files in cairo.
Merge pull request #1 from tangbo2013/develop

xCairo已完成移植。
modify folder: iOS
remove cairo empty impl .c files.
Merge pull request #4 from tangbo2013/develop

remove cairo empty impl .c files.
remove font/glyph interface
remove font/glyph
Merge pull request #3 from guangbin79/remove_font

remove font/glyph
modify cairoint.h