CRM-15297 add extra d8 permission functions.
The ones not customised to D8 (per https://github.com/torrance/civicrm-drupal/commit/9e9e4e2e344f500cd083a2af4a68f4fe25ae4e5d#diff-e446ed2bd1f533a810378b76b9ec7312)
are add to the DrupalBase class
CRM-15297 add Drupal8 functions from GSOC to Drupal8 class
where the d8 function is unchanged from d7 put in the DrupalBase class instead
CRM-15297 - move default block to d8 class as default in base class is 'left'
(NB defaultBlockLocation may be drupal specific & not really belong in baseclass
Merge pull request #4410 from eileenmcnaughton/CRM-15297

CRM-15297 drupal 8 integration