RzAnalysisILVM wraps around the low-level RzILVM and enables emulation
of real code from disassembly, rather than raw IL.
Analysis plugins now don't actively initialize the vm anymore, but
return a fully declarative description RzAnalysisILConfig of how to set
up the vm and optionally its initial state.
This also enables multiple IL vms to exist at the same time as plugins
can not mess with the global vm anymore. See the added integration test
for an example.
