[bennu-admin] Completely rewritten the bennu-admin application

  * It is now built using Angular.js instead of Bankai
  * Updated to work with the new version of bennu-portal
  * Greatly improved the System Info panel, showing more JVM information and allowing Thread Dumps
  * Added a simple DomainBrowser UI, that allows navigating through the instance graph of the application

Rewritten bennu-admin to comply with the new bennu-portal

[bennu-admin] Greatly improved System Info panel

  * Added Domain Browser functionality
  * System Info now shows more JVM information and allows Thread Dumps