Rudimentary attempt at remote divergence segment
hide divergence segment if none
Add basic kerl invocation
Change diverged symbol
First draft of vcs_info segment
Attempt to fix up guess/2 calls
use a slightly shorter highlight name for vcs_status
Add overall vcs_repo_status:clean flag
Correctly add general clean flag to vcs_info
highlight_groups for kerl, divergence, vcs_status