No longer using vim-rvm
Add nvm initialization
Update git aliases

Add new git aliases that I've grown to rely on.
git graph for pretty version graphs
git hist for pretty history information
'git gr' and 'git hi' as shortcuts for the above.
Default setting for ruby set to expandtab
Set rspec defaults

I've come to expect and prefer progress style
rspec formatting with color. Lets make it my
default shall we?
Save my tmux config to dotfiles.