[bennu-core] Improvements to the Bootstrap process

  * Added missing resource
  * Better handling of exceptions
  * Usability improvements
  * Bootstrap errors now properly cause the process to be aborted
[bennu-portal] Add missing resources
Removed deprecated AuthenticationListener in favor of the synchronous version
Remove cross application server session invalidation
Removed accessibleGroups() feature
Add checksum to GenericFile
Create the concept of default file storage to handle unconfigured files
Reviewed group mechanics, separated persistent part from the group logic. Reviewed group language, now using antlr4 and solved all parenthesis issues. Improved error handling.
Extended file API to include an isAccessible(User user) method. New file type: GroupBasedFile that implements isAccessible with a Group
Migration instructions
Since bootstrap authenticate does not need to bootstrap the first user and the managers group