DO NOT MERGE: Perform alias analysis in C/C++ dataflow

[MathiasVP]

This is my ongoing work related to adding dataflow through aliased definitions in C/C++ dataflow. For example for something like:

int x;
int* p = &x;
x = source();
int y = *p;
sink(y);

on main there won't be any dataflow from source() to the sink argument, but on this branch we'll have that dataflow.

This is still a WIP since:

1. It has a 15-20% performance regression on DCA that I'm still battling, and
2. It still has a few cases of pointer/pointee conflation (i.e., we mistake an int* for an int and vice versa).

I'm leaving the PR open here for others to experiment with it.