walde: maintenance

[Noki]

• [ ] walde-core
  • [ ] get / set password of walde-core
  • [ ] document the password
  • [x] add mesh interfaces to fritzbox so there could be local meshing
  • [ ] flash new firmware
• [ ] walde-emma
  • [ ] get access and setup management ip & vlan
  • [ ] add to UISP
  • [ ] update firmware