Squashed 'bundle/vim-pathogen/' content from commit 1b644bf

git-subtree-dir: bundle/vim-pathogen
git-subtree-split: 1b644bf4b263b8ce65a35fc6fa5e541813cd9efc
Merge commit 'f0937be313745dd5336250f7305112b7ac2d2a60' as 'bundle/vim-pathogen'
Add github-plugin-install.sh