Don't respond to duplicate keyboard notifications

Closes #48
Add explicit method to calculate content size from contents; slight refactor; don't pad width
Updated project settings
Refactored primary functionality into a category to avoid code duplication
Fixed view coordinate mismatch
Renamed a method for clarity
Addressed an issue with table view on iOS 7; clarified some code; fixed a couple incorrect instance variable references
Fixed a namespace conflict issue
Moved some things around, updated pod spec for v1.2
Fixed a few issues affecting insets and offsets in orientations other than portrait.
Merge pull request #51 from timvandekamp/master

Fixed a few issues affecting insets and offsets in landscape
Pending further fixes, Revert "Fixed a few issues affecting insets and offsets in orientations other than portrait.", which breaks portrait

This reverts commit 5518a74a0688a071a2d7defec3c0f56da893bfb2.
Fixed a few issues affecting insets and offsets in orientations other than portrait.
Potential fix for insets and offsets for landscape without breaking portrait
Cleaned up prior commits slightly
Updated podspec for 1.2.1
Scroll performance fix
Only set text field return key type if it was set to UIReturnKeyDefault

Closes #54
Fix compiler warning when GCC_WARN_ABOUT_MISSING_NEWLINE is enabled
Merge pull request #62 from chucks/missing_newline

Fix compiler warning when GCC_WARN_ABOUT_MISSING_NEWLINE is enabled