LU-13971 quota: report Pool Quotas for a user

LU-13971 quota: report Pool Quotas for a user

Patch adds ability to show quota limits and usage
from all pools per user. Since this patch
long option --pool without argument results
in printing Pool Quotas for all known pools:
lfs quota -u quota_usr --pool /mnt/testfs
Pools from lustre:
Quotas for pool: qpool1
Disk quotas for usr quota_usr (uid 60000):
     Filesystem  kbytes   quota   limit   grace   files   quota   limit   grace
    /mnt/lustre       0       0   10240       -       0       0       0       -
Quotas for pool: qpool2
Disk quotas for usr quota_usr (uid 60000):
     Filesystem  kbytes   quota   limit   grace   files   quota   limit   grace
    /mnt/lustre       0       0   20480       -       0       0       0       -

To get information for specific pool you still
need to set pool name after --pool:
lfs quota -u quota_usr --pool flash /mnt/testfs

Patch also adds sanity-quota_74 to check new
feature.

Test-Parameters: trivial testlist=sanity-quota
HPE-bug-id: LUS-8720
Change-Id: Ib918eef84c2352946ce13342471f36e2b500df32
Signed-off-by: Sergey Cheremencev <sergey.cheremencev@hpe.com>
Reviewed-on: https://review.whamcloud.com/39975
Reviewed-by: Petros Koutoupis <petros.koutoupis@hpe.com>
Tested-by: jenkins <devops@whamcloud.com>
Reviewed-by: Wang Shilong <wshilong@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>