Ignore QtCreator user files
Do 'remote update' rather than 'pull' for update target.
Enable support for specifying type of repository 'update' for GIT.  Options are: "REMOTE_UPDATE", "FETCH_MERGE", "CMAKE_DEFAULT", and "NONE".  "FETCH_MERGE" is the old 'git pull' behaviour; "NONE" is the new default.
Renamed REPO_UPDATE_TYPE to REPO_UPDATE_POLICY
Documented REPO_UPDATE_POLICY
Fix #90 and CR #89 as per discussions in issues