Move functions into a subfolder

This makes room for the fish_completions folder
Add git flow completions
Add mark functions (slightly modified for Fish)

Source: http://goo.gl/Oc5tMT
Add e function for opening things with the $EDITOR
Don't bother me with details, just mkdir!
Wrap git with hub for easy access to GH features
Add more confusing flags to `ls`
Add completions to the jump command