.gitignore: Don't ignore Git/{gpstools,suuid,svnutils}/ anymore

dafdae10-e3be-11e2-9def-0800274013ad
Use submodules for Git/{gpstools,suuid,svnutils}/, fetch from GitHub

4070f8b4-e3c0-11e2-a565-0800274013ad
Merge branch 'use-submodule'

* use-submodule:
  Use submodules for Git/{gpstools,suuid,svnutils}/, fetch from GitHub
  .gitignore: Don't ignore Git/{gpstools,suuid,svnutils}/ anymore

bdcb2ea6-e3c0-11e2-8096-0800274013ad