Unbreak relevant-tests interaction in git_hooks
Unbreak relevant-tests interaction in git_hooks

This has been broken since we moved to RSpec 2 because the formatter is
returning absolute paths where it used to record relative ones.

Fix that by converting everything to an absolute path before converting.

Related story:
  http://www.pivotaltracker.com/story/show/29431853 (fixed)
  ("Unbreak relevant-tests interaction in git_hooks")

Change-Id: I8c6abbd8f654b98d5391ee499bab8cab18b394e0
Reviewed-on: https://gerrit.causes.com/6566
Reviewed-by: Greg Hurrell <79e2475f81a6317276bf7cbb3958b20d289b78df@causes.com>
Tested-by: Greg Hurrell <79e2475f81a6317276bf7cbb3958b20d289b78df@causes.com>

TheSooth/overcommit,blech75/overcommit,gnagel/overcommit,blech75/overcommit,oxocode/overcommit,gnagel/overcommit,oxocode/overcommit,TheSooth/overcommit