Tooling improvements

[ttreyer]

Summary

Fixes & QoL:

• OIP: Fix TypeHierarchy deserialisation
• OIP: Print 'this' as an argument for methods
• OIP: Print location expressions of arguments
• OITB: Add support for -f/-F feature flags

Also introduce the new tool oirp to read the content of OID's output RocksDB.

Test plan

No change to oid.

$ make test
...
99% tests passed, 1 tests failed out of 572

Total Test time (real) = 180.18 sec
...
The following tests FAILED:
        112 - integration_py (Timeout)

[tyroguru]

Excellent - thanks Thierry.

We could probably do with a README file in the tools directory which details what the different tools are for preferably with examples of their usage.