0.7.0: Nyan Cat

Thanks to @norio-nomura & @1ec5 for the much needed bug fixes in this release.

Breaking

• File is now a final class instead of a struct and contents & lines
  are now marked as var. This was done so that mutations to the underlying
  file on disk can be mirrored in a File instance.
  JP Simard

Enhancements

None.

Bug Fixes

• Fix issue where Swift extensions would pick up documentation from previous
  tokens.
  JP Simard
  #65
• Fix String.stringByTrimmingTrailingCharactersInSet(_:) returning full string
  when all characters matched character set.
  JP Simard
• Fix indexOfByteOffset(offset:) failing when string include some emoji.
  Norio Nomura
  #111
• Fix pragma mark extraction with multibyte characters.
  1ec5
  #114