File ownership for ebs_raid resource mount_point

Currently the ebs_raid resource does not provide the ability to specify file ownership and mode for the RAID device mount point (the ownership and mode is hardcoded to root/0755).

An example where this would be useful is when creating an EBS raid array and mount point for PostgreSQL, earlier in the run list in order to mount a data directory and symlink it to /var/lib/postgresql so that the default PostgreSQL data_directory does not need to be changed.