Updated Xcode template.
Added restriction marco `CC_TARGET_PLATFORM == CC_PLATFORM_MAC` for CCEditBox of MAC port.
This can avoid compilation errors if other platforms include these files.
Merge pull request #1845 from dumganhar/gles20

Updated Xcode template.
Also, added restriction marco CC_TARGET_PLATFORM == CC_PLATFORM_MAC for CCEditBox of MAC port.
This can avoid compilation errors if other platforms include these files.