Rewrite msgSend calls with known receiver type

[fmagin]

With the types injected by #15 Ghidra's regular type analysis will then run and should propagate these types forward to msgSend callsites.

This means we can write another analysis that uses the decompiler, to now check for the type of the first argument to a msgSend call which will not always be just ID anymore. It can then look up the class_t struct for that type and search for the function implementing the selector (from the second argument).

Ghidra can then be told to rewrite this msgSend call to a call to the actual implementing function:

val reference = program.referenceManager.addMemoryReference(
                    msgSendCallsiteAddress, implementationAddress,
                    RefType.COMPUTED_CALL, SourceType.ANALYSIS, 0)
program.referenceManager.setPrimary(reference, true)

Should run as AnalysisPriority.DATA_TYPE_PROPOGATION.after(), unclear as which AnalysisType.FUNCTION_* exactly