Remove whitespace.
Use my_internal_ip_address for fetching IP address.
Steal history configs from @jferris.
Drop Powerline for Airline

Powerline is kind of a performance hog. Airline is all vimscript, and
seems to be faster and incorporates the status line items that I want in
vim and not in tmux without any customization to get going.

Dropped powerline-specific configs and timeout hack.