Panels everywhere support

Hi all!
I've modified theme to make it compatible with Panels/Panels everywhere modules.

Features:
- site template layout for basic Bootstrap layout
- sample site template panel with appropriate layout (just enable it on /admin/structure/pages page)
- style plugin for dropdown menus
- compatible with old, blocks-oriented code

I want to continue integration and plan to make a flexible layout to have possibility to configure Bootstrap's grid, implement some of Bootstrap's elements as content types/style plugins.
So if available add me to co-maintainers, and i will merge all my code.

In attachment patch for current version, and whole variant of my version of theme (if patch will fails for someone...).
Also note that this patch contain another my fix from this issue - #1686342: Double bootstrap.js addition.