Revert to default Git log style

* Our current style hides message details
* Default style shows details and one-line versions as appropriate
Start tmux window numbers at 1

The keyboard from left to right is 1 2 3 4 5 6 7 8 9 0. Make tmux
windows match this order.
Update git's push.default from tracking to upstream

The 'tracking' value has been deprecated in favor of 'upstream'.
Renumber tmux windows after closing any of them
Add e alias for $EDITOR, v for $VISUAL

* Goal is to quickly open current project in vim to v.
* This is a dozens-of-times-per-day kind of task for me.

Lively discussion here:

https://github.com/thoughtbot/dotfiles/pull/100