Util_Reas_Grp

Rename the "class_id" field to "parent_reas_grp_id" to support having multiple levels of reason groups.

Remove the foreign key from "class_id" to util_reas_grp_class and add a foreign key from "parent_reas_grp_id" to util_reas_grp to support having multiple levels of reason groups.

Add "spare1" through "spare4" (string80, nullable) before "last_edit_comment" to provide a place to put data that had been in the "spare1" through "spare4" fields of the now obsolete util_reas_grp_class table.

Add "parent_reas_grp_id" to the unique key, allowing reason groups with the same name to appear under different parents.