WebUI improvement:

Main page:
- Change page title to "ETSI TeraFlowSDN Controller"
- Add slogan "Open Source for Smart Networks and Services" next to the logo (on top)
- Change Logo and Icon

About page:
- Change title to "ETSI TeraFlowSDN Controller"
- Remove link "TeraFlow H2020 webpage" and add link "ETSI Open Source Group for TeraFlowSDN" pointing to: https://tfs.etsi.org/
- Remove partners logo

Service detail page :
- Show correct Service Type instead of integer
- Show service status
- Format configurations as in device details
- Format constraints as in device details
- Add constraints
- Format endpoints and add device uuid

Service page:
-Remove constraints

Link detail page:
-Add device uuid to the endpoints table