Poplate akonadi_google_resouce from an existing file
- rename akonadi_googlecalendar_resource as akonadi_google_resource and add a compatibility mapping for stable5;
- technically akonadi_googlecontacts_resource may have relevant message, but simplify the licensing issues from merging by just using one file. akonadi_googlecontacts_resource will go away when release/20.08 is branched.