LU-1842 quota: lfs quota commands

LU-1842 quota: lfs quota commands

- Removed 'lfs quotachown' & 'lfs quotainv';
- For 'lfs quotacheck', 'lfs quotaon' & 'lfs quotaoff', print
  proper message when -EOPNOTSUPP returned from 2.4 server;
- Updated man page for lfs quota commands;
- Removed quotainv from test_15 of s-q;

Signed-off-by: Johann Lombardi <johann@whamcloud.com>
Signed-off-by: Niu Yawei <niu@whamcloud.com>
Change-Id: I89e6d1e981640ab0f62e10bc5a91946c78644cc3
Reviewed-on: http://review.whamcloud.com/4022
Reviewed-by: Fan Yong <yong.fan@whamcloud.com>
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>