Small update for co-browsing

• Option to disable iframes rendering. It just increases security in some cases. There is checkbox in co-browsing settings page.
• href links in co-browsing will be replaced with javascript:void(0), so in order operator to click invalid link he will have to type it manually.

For update just follow standard update procedure For manual update it's update_121.sql

P.s sorry all forum users. I'm just overloaded. I'll get back to you all after few weeks :(