Add test setup for alias analysis

[LukasKlenner]

This PR adds a setup for testing alias analyses, including some (simple) test cases.

More (complex) test cases alongside analyses that pass them will be added in future PR's. This is a continuation of #171

[errt]

Build doesn't work for several reasons, please fix

[LukasKlenner]

building issues are fixed, but it fails because the AliasTests don't pass, despite them being annotated with @Ignored. Is it not supported or is something else required to make the tests not being executed?

[LukasKlenner]

PS: AliasEntity and AliasSourceElement need to be in the tac package (and not br) because they rely on the DefinitionSite class

[errt]

PS: AliasEntity and AliasSourceElement need to be in the tac package (and not br) because they rely on the DefinitionSite class

This may hint at potential to improve. In many cases, we map TAC use sites to bytecode program counters and values (search for persistentUVar), a similar mapping, maybe even excluding the values, might be applicable here.

[LukasKlenner]

All previous issues have been addressed, but most of the classes have been completely reworked