Add configurable API endpoints to server and node (#245)
Define /node/cert as alias of /node/api/cert (#245)
Fix node <-> nodeApi cardinality (1<-->0..1) (#245)
Create related default api for existing objects (#245)
Define deletion behaviour for ServerApi (#245, #487)
Merge branch 'master' into feature245
Fix Api serializers cardinality (#245)
Update database to define deletion behaviour (#245 + #487)
Drop do-request-cert, create do-request-mgmt-cert (#234 note-19)

* Provide certificate signature as utility (do-request-mgmt-cert)
* Generate node.api.cert on firmware generation.
Fix node.api @setter: allow set /api to null (#245)
Provide Api object creation with default base_uri (#245)
Delete node.cert field (#245)
Node go DEBUG on api missconfiguration (#245 note-21)
Provide default URI when adding an API endpoint to a node (#245 note-21)
Cosmetics: mix node advanced fieldset with the main one.
Remove form that forces mgmtnet creation.

As mgmt_net is alreday created on demand,
is not neccesary this tricky hack.
Materialize TincHost.name attribute.

Having 'name' stored in the database will help
backwards compatibility on #236 for existing
gateways and server.
Merge branch 'master' into feature245

Conflicts:
	controller/__init__.py
	controller/apps/mgmtnetworks/admin.py
	controller/apps/mgmtnetworks/models.py
	controller/apps/nodes/admin.py
	controller/apps/nodes/api.py
	controller/apps/nodes/models.py
	controller/apps/nodes/settings.py
	controller/apps/nodes/tests.py
	controller/apps/nodes/validators.py
	controller/apps/pings/tests.py
Merge branch 'feature236' into feature245
Add multiserver support (#236)

* Several servers can be created.
* Update addressing schema.
* Migrated existing one to have pk=2 to keep backwards
  compatibility with existen mgmt_net address.