Generate a callsite identifier associated with each callsite

1. Generate a unique string name for a callsite that appears in every node
2. This identifier will refer to a single callsite and is used for trace data retrieval

@ke-yu
@lukechurch
@Steell
@Benglin

Ive created the bug. And thanks for catching this, discrepancy. It does work for multiple lines in a CBN. It only fails when you manipulate the lines of code in a CBN and attempt to retrieve the cache callsites