ceph: propagate do_command()'s return value to user space

We were returning '1' regardless of what do_command() returned in case
of error.  This would make building tools relying on command error codes
short of useless, and forced them to rely instead on error messages.

Signed-off-by: Joao Eduardo Luis <joao.luis@inktank.com>
Reviewed-by: Dan Mick <dan.mick@inktank.com>
ceph.spec.in:  Move four scripts from sbin to usr/bin

The ceph-create-keys, ceph-disk, ceph-disk-activate, and
ceph-disk-prepare scripts are built in sbin, but debian installs
them into usr/bin, and several utilities look for them there.
This commit changes the RPM to install them in /usr/bin. (Bug #3921)

Signed-off-by: Gary Lowell  <gary.lowell@inktank.com>
Merge git://github.com/ceph/ceph