Open file containing current chunk from 'pull-request' view

mapped to ,,o

1. Move cursor anywhere inside code chunk like this in 'pull-request'
view on the right panel.

       def report_email(user, project, activities)
    -    @user        = user
--> +    @user        = UserDecorator.new(user)
         @activities  = activities
         @time_period = time_period
    +    @today       = today

2. Push ,,o

3. The file, containing code chunk will be opened with Gblame and
highlighted code chunk.