The API URL must be adapted in a Vagrant box environment

The current API URL is <IPADDR>/openattic/api, but must be changed to <IPADDR>:8000/api in a Vagrant box to be able to access the API view via browser and to allow API calls between nodes in a multinode setup.

Note: In a Vagrant box the WebUI is not delivered via the Apache Webserver, instead the Python webserver is used which is started on port 8000 by default.