Remove railscast-theme subtree
Squashed 'vendor/railscasts-theme/' content from commit d8c5612

git-subtree-dir: vendor/railscasts-theme
git-subtree-split: d8c5612c71508712ea2cd8523d4af863ef86a106
Merge commit '040079b24c01c7c4bb8c54dc86a8a879ae36ffc2' as 'vendor/railscasts-theme'
Load railscasts theme after adding it at the correct prefix.