Add link to tinc addresses under tinc configuration. refs #603
Merge branch 'master' into feature603
Fix get_default_gateway max recursion depth on particular context.
Fix ServerApi initial data creation. refs #245.

Create main server before ServerApi initialization, otherwise
ServerApi is not initialized for main server.
Remove ServerApiInlineForm: custom validation is no longer required.
Fix test_get_default_gateway (be sure that there isn't any server)
Fix raise PermissionDenied on delete last server instance. refs #236.
Mark if sliver set_state cames from sliver defaults.

Improve UX - refs #234 note-91.
Fix tooltips for sliver set state (#234).

Previous code didn't take into account if different sliver set state was below
the slice's.
Merge branch 'feature603'
Merge branch 'master' into feature470
Add firmware plugins config via API. refs #470.