Move vim abbreviations and keymaps to spearate files.
Have git ignore vendor/bundle directories.

This is where we have Bundler store per-project gems.
Update install script to include vim abbrev and keymap files.
Enable relative line numbers in vim.
Store vim backup files in one place.
Have vim cursor keys and selection work more like normal Mac/Windows programs.
Fix extraneous output when testing for rbenv.
Add NPM package binaries to $PATH.
Steal adkron's vim keymaps.