LP1851831 Group perm editor null descriptions OK

LP1851831 Group perm editor null descriptions OK

Avoid assuming a permission description value is non-NULL in the
permission group editor interfaces since values are not required in the
database.

Fixes: ERROR TypeError: "l.description(...) is null"

Similarly repair the permission list title attributes so they display
the permission code (instead of an empty string) for titles when no
description is available.

Signed-off-by: Bill Erickson <berickxx@gmail.com>