Closes #410 - adds ability to search by multiple criteria
Adds ability to match case, match all, & use regex

Fixes issue with wrong diff line with previous
Fixes issues with previous/next when on right/left side of diff editor

Adds last fetched on date to fetch & pull
Adds fetch button to pull
Adds behind/ahead commit counts to pull/push respectively

Adds last commit date to branches

Changes working tree/branch comparision selection to be per-comparison

Replaces "recent incoming changes" node