(Binary Analysis) Split instruction matching from function matching
(Binary Analysis) More work on x86 PE partitioning

Changes to support thunks:

* Added the E_FUNCTION_XFER edge type to represent transfer of control
  from one function to another without a function call.

* Recognize LEA-JMP combination as a thunk

* Function prologue matches can instantiate multiple functions

Additional function prologue patterns

* Recognize RET+PADDING+PUSH as a function at the PUSH address