Long story short: we don't want contrib code inside src/opnsense/contrib
so a few things need to be shuffled.  First pass is moving the current
contrib stuff to the same location instead and migrating the non-code
tzdata file.

o Can't unset the session var anymore resulting in permanent
  login error message display until login was successful.
o Remove some padding and make permanent room for the error
  message so that the container doesn't grow after submit.
o Move the workaround to a permanent position in <button/>.
o Move the copyright right line right underneath the container.

(config) automatic recovery when config is broken, closes https://github.com/opnsense/core/issues/701

note: there's no trigger to perform the sync, so currently differences are only synced in the slipstream of otther events.
The events around synchronisation and reloading services really need some work sometime....

translation fixes

* XMLRPC: Special characters should be preserved, closes https://github.com/opnsense/core/issues/596
* XMLRPC sync only works if both systems have the same GUI port configured, closes https://github.com/opnsense/core/issues/125
* remove unreachable code