tmux: bind hjkl to select panes

I have been using arrow keys only to switch tmux panes, along with the
occasional mouse click. However, I noticed that my fingers have been
wanting hjkl in addition to arrow keys. I would consider just disabling
the arrow key bindings, but since I use Colemak, hjkl aren't always the
most convenient things to hit either.

This change is nice because it makes my overall configuration a little
more consistent.
Revert "Add wombat color scheme to vim"

In my commit message I mentioned that I added this as a backup to
solarized. However, I don't think I've used it once since adding it, so
I decided to remove it to clean out the cruft.

This reverts commit 13efe122261a4347a5bc8bb00c4c753c12d8d4d9.
Git: clean out .gitconfig

There was a bunch of stuff in here that I never use, so I decided to
clean it out. There is likely even more that I could get rid of here,
but I figured I would just start with the obvious stuff.