Scrum index page

This incorporates pull request #429:
* created new page for scrums listing scrums/index
* created a timeline for scrums
* added gem youtube_it
* added gem VCR
connected with comment above: 
better: 
```
module Youtube
  YOUTUBE_KEY = ENV['YOUTUBE_KEY']
end
```
while ENV['YOUTUBE_KEY'] is initialised manually if env = test or development and by travis in production.
See initializers/omniauth.rb