dashboard.py: better fetching and handling of dashboard data
The dashboard fetchs the data using the REST API in three different requests while I write these lines. This means there might be some issues with data syncronization and it'd be good to implement an endpoint (e..g /full-state) with atomic data or look for another ideas.
The data obtained from the REST API is stored in a dictionary with minimal processing. This is working reasonable well now we have little data and are not adding a lot of fields but we need to look for a better solution. A good solution might be to do the same that valvetraces.