Integrate terminus_store_prolog directly into TerminusDB

[matko]

This pull request directly integrates store into TerminusDB, allowing reuse of blob types.

It pulls in the relevant source code from terminus_store_prolog, allowing us to drop this dependency. This also means the container now builds directly on top of the swipl container, rather than on top of the terminus_store_prolog container.

[matko]

I pre-squashed a whole bunch of commits to make this somewhat easier to review. There's now 3 commits with changes.

1. Alter the build to include building terminus_store_prolog (taken in from a git repo, not yet merged into the source), and set up the environment to make use of it.
2. Actually pull in all of the terminus_store_prolog source directly
3. Update the Dockerfile to build on top of the swipl container, instead of the terminus_store_prolog container