Query service url asynchronously
Add some error handling
Add refresh button
Center status image horizontally
Implement layout for led board service
Implement layout for door service
Rename everything 'relais' to 'relay'
Start working on layout for web relay service

Still kind of messy. Needs more work on custom composite views
Add unknown status
Finalize layout for web relay service
Add CHANGELOG
Raise version to 0.2.1