Install Vundle Vim plugin manager

See https://github.com/gmarik/Vundle.vim
Clean up .vimrc
Ignore .vim/bundle plugins directory

The subdirs here are managed by Vundle itself; no need to check anything
in.
Remove example Vundle plugin configuration
Revert ignoring Vundle plugins

... because they're actually submodules.
Add vim-jekyll plugin
Work around Vim issues caused by Vundle plugin

See https://github.com/gmarik/Vundle.vim/issues/167#issuecomment-49139196
Override $LANG environment variable; set to en_US
Update vim-jekyll with my customizations

See new fork of vim-jekyll repo at
https://github.com/cbeams/vim-jekyll