Drupal region padding in _layout.scss does not integrate with Bootstrap vertical rhythm

This patch version applies against latest 3.0-dev and set $region-padding default to 0 and removes the already rendered css regarding this variable from the compiled styles.css. I think this is the best attempt with the most flexibility so the user can later decide to increase it again if required and recompile. But the default should definitely be 0 to go with the flow of Bootstrap grid and vertical rythm, IMHO.

I'm not sure the .region classes listed above are the only place where extra padding has been added. I am also seeing that .footer has been set to have padding 2rem 0 which is adding lots of white space above and below anything with the class "footer".

Another unexpected change is that .navbar-brang img now has a fixed height of 60px, which I cannot understand - is this another change new to the .scss files?

Strictly speaking all of this can be worked around in my subtheme by changing the values of the variables referenced in the various .scss files, but that should surely not be necessary to adapt to a minor new version of this theme.

review on v4