Add default user/group/project quota properties

This adds default userquota, groupquota, and projectquota properties to
MASTER_NODE_OBJ to make them accessible during zfsvfs_init() (regular
DSL properties require dsl_config_lock, which cannot be safely acquired
in this context). The zfs_fill_zplprops_impl() logic is updated to read
these default properties directly from MASTER_NODE_OBJ.

Signed-off-by: Ameer Hamza <ahamza@ixsystems.com>

Reviewed-by: Alexander Motin <mav@FreeBSD.org>
Reviewed-by: Tony Hutter <hutter2@llnl.gov>