Implemented New Category settings - Tabs 1-5 Options: Min & Max Message Length

A per title, I've added some New Category settings to the Tabs 1-5 Options. Theses new settings allow you to set the Min & Max Message Length for EACH Tab's Editor.

This is a long overdue feature for Showcase that will now allow Admins to prevent the cases of Items being created without entering content for Tab 1.

Default (Unset) is Min: 0 (Zero) and Max: 25,000

NOTE: The Item Page "Max Message Length" option has been removed. These settings are completely controlled on a per category basis (if you don't initially set them, they will use the default values above).