Repair and stylization BB-CODE HIDE

Changed sql query when creating HIDE, changed style class that is
assigned ( .hidden ) A linguistic variable is derived in templates for
easy design of hidden text
Make changes on a recommendation from Kort

Make changes on a recommendation from
# 38791 Kort:
Change the names and the variable lang-class hidefromguests and restore
the original.
http://www.cotonti.com/forums/38791?m=posts
BB-CODE HIDE repair and stylization

Changed SQL Query to create BB-Hide, adding linguistic variable $ L
['hidefromguests'], change the class .hidden on .Hidefromguests, adding
css style for the class .hidefromguests
Merge pull request #1304 from Justwebber/master

Repair and stylization BB-CODE HIDE