switch to antigen for some stuff.

- also move path setting to speed some things up
- also add some timing logs for debugging slow startup,
  and do a bit of cleanup to speed up startup (approx negates the slowdown
  from antigen)
clean up and speed up prompt.

- also fix issue where sometimes prompt didn't show insert/normal state
  properly
- use different colors for highlighting
don't double-source bash aliases
improve gmod function
clean up keybindings using terminfo.
ignore bundles from antigen.
fix failure logging.