Feature/compute callcount

[MalinAhlberg]

Describe the pull request:

• [ ] Bug fix
• [X] Functional change
• [X] New feature
• [ ] Code cleanup
• [ ] Build system change
• [ ] Documentation change
• [ ] Language translation

Pull request long description:

Move the calculation of callcount from psql to python import (--count_calls) This speeds up queries to the beacon metadata, which no longer needs to be materialized. Also improve the sql schema so that no views are materialized.

Changes made:

1. Calculate the dataset's callcount and variantcount on import
2. Make data_table a real table
3. Stop materializing views
4. Add better indices