mon/MonCap: remove useless 'osd crush add' perm from profile bootstrap-osd

Bootstrap doesn't use or need this; the crush update happens when the osd
starts up (see init-ceph or upstart/ceph-osd.conf).

Signed-off-by: Sage Weil <sage@inktank.com>
mon: clarify 'osd crush add' vs 'osd crush set'

Signed-off-by: Sage Weil <sage@inktank.com>
mon: OSDMonitor: don't expose uncommitted state on 'osd crush link'

Fixes: #4635

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Joao Eduardo Luis <joao.luis@inktank.com>
mon: OSDMonitor: document 'prepare_command' wrt expected behavior of no-ops

Signed-off-by: Joao Eduardo Luis <joao.luis@inktank.com>
mon: OSDMonitor: don't expose uncommitted state on 'osd crush add/set'

Fixes: #4635

Signed-off-by: Joao Eduardo Luis <joao.luis@inktank.com>