Consistent variable dereferencing.
Show remote if it's not the same as the local.

So if a remote shows up, you need to set upstream with `git branch --set-upstream-to=origin/...`.
It's generally annoying to see this displayed, which means there's incentive to fix the upstream.
Explicitly get branch name, in case it's been modified by another hook.
Consistent colorizing, function calls, formatting, style, etc.