Doc comments.
Merge branch 'master' of https://github.com/pilgrimagesoftware/Snapper

* 'master' of https://github.com/pilgrimagesoftware/Snapper:
  Hashtag search operation initializer wasn't setting hashtag property.
  Added missing headers.
Merge branch 'master' of https://github.com/pilgrimagesoftware/Snapper

* 'master' of https://github.com/pilgrimagesoftware/Snapper:
  Added "is_leading" property.