LU-2740 utils: Add support for --version option

For mount.lustre, mkfs.lustre, lfs, and lctl, a
--version option was added that will print the
LUSTRE_VERSION_STRING.

lctl has an option called lustre_build_version that prints
both the Lustre version and the lctl version, which is
BUILD_VERSION. Printing the lctl version was removed from
the 'lctl lustre_build_version' output since
BUILD_VERSION and LUSTRE_VERSION_STRING are very different
strings and this could be confusing to the user.

Also, mount.lustre and mkfs.lustre prints the version number
when printing help/usage. This was removed to make all
Lustre utilities have a more uniform output.

The lctl, lfs and mkfs.lustre man pages were updated to include
the --version option.

Signed-off-by: James Nunez <james.a.nunez@intel.com>
Change-Id: I301258562f51640f041dd7ac6aa695450270c385
Reviewed-on: http://review.whamcloud.com/11014
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>