LU-7835 checkpatch: Update gerrit_checkpatch for new features.

LU-7835 checkpatch: Update gerrit_checkpatch for new features.

Allow checking of a single patch per invocation rather than running as
daemon. Update wiki URL for coding standards. Supply --notree option
allowing upstream checkpatch.pl to be used. Add linebreaks to output
when reporting multiple errors per line of source

Signed-off-by: Ashley Pittman <ashley.m.pittman@intel.com>
Change-Id: I3823db55073b606fb84b84f520e598e8427b22e7
Signed-off-by: Ashley Pittman <ashley.m.pittman@intel.com>
Reviewed-on: http://review.whamcloud.com/18748
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>