E3-414: Update table view

Modifies the "Table" page to fetch data (including the correct pipeline status) from Gitlab instead of the NFS.

There is a lot that could be improved here, potentially, and we lose the versions that are installed. However, it does produce a nice shiny page that shows the status of all of the pipelines, so that's cool.

Unfortunately, GraphQL queries for gitlab at the moment do not seem to permit fetching tags, only "releases", which we have not been using. So there isn't an obvious way to show which versions of base/require are supported, other than either

• parse the NFS
• use the python-gitlab module in addition to the GraphQL API to explicitly fetch tags

Still, this seems a good start.