Refactoring.

API clean up, better JSON parsing, better atlas, easier to extend.
Readers, not streams.
Merge branch 'master' into monogame
Fixed crash with no newline at start of atlas.
Update spine-cocos2dx.cpp

Fixed crash at bounding box function.
Merge pull request #30 from flaming0/patch-1

Update spine-cocos2dx.cpp
Merge branch 'master' into monogame