Merge branch 'develop'
Fixed trivial problems.
Added the property for subclass.
Removed old codes.
Add code to cancel selected texts when user taps the region which does not any links.
Refactoring.
Added comment.
Moved the pre-compile header file.
Update comments.
Refactoring for warning.
Refactoring drawSelectedTextFragmentRectsFromIndex:toIndex:color:.
Rename, circumscribingRectForStringFromIndex:toIndex:.
Fixed auto layout warning.
Fixed compiler warning.
Documentation and change compiler warning setting.
Added comment.
Added comments.
Updated documents.
Merge branch 'feat-doxygen-documentation'
Added a margin around content area.
Adjust cursor size.
Apply margin function to sample application.