Scald reports - redux

Now that the reports have been switched over to use ligo-scald, I took some time to add a theme to the report so that it looks closer to the DQ summary pages by using some new components added to scald. Some unused methods were also removed as a result of this.

Environment has also been updated to point at a pre-release of scald until a new version is released.

Finally, fixed an issue with idq-monitor causing test failures. The pre-release of scald had removed the hdf5 backend of the aggregator which we don't use anyways, so clean that out.