Merge pull request #1 from Chun-Yang/master

vimrc: Modify airline status bar. Add current line number to the left of current line.
Merge pull request #2 from Chun-Yang/master

airline status bar: show percentage of current line, remove deliminator
Merge pull request #3 from Chun-Yang/master

speed vim up when editing ruby files by changing regex engine
Fix bundle name not being updated to accurate repo name
In tmux, use C-a C-a to output C-a, set wait time to zero when we hit escape