[#3] new: Add strip_slash function for Octopress.

Closes #3.
[#4] new: Add shorthand_url function for Octopress.

Closes #4.
[#5] new: Add Octopress#titlecase().

Closes #5.
[#6] new: Add Octopress#category_link().

Closes #6.
[#7] new: Add Octopress#category_links().

  Closes #7.
[#8] Add Octopress#raw_content().

Closes #8.
[#9] Add Octopress#expand_urls().

Closes #9.