Update of Selenium IDE add-ons

1. I've added a new add-on: SeLite Run All Favorites
2. I've created a new small "SeLite" section just before the first SeLite add-on. Then I've removed duplicate SeLite-related text from all SeLite add-ons. I belive the look fits in and is not intrusive.

This is for https://code.google.com/p/selenium/issues/detail?id=7855.
Thank you.