Truffle/Instrumentation:  API revisions
Merge with 2f684eda1938cc92a72a35461c8d00f1871fe389
Backed out changeset: d44e138f7020

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extra : amend_source : 6f300100f085bdd430840e08ba7202dfedb4b4d9
Truffle: use PiNode for unsafe type casts
PiNode: merge object stamps using castTo
Merge with cb2eef41371c7e61e16c0076b0a1ad855dab86cc
switch MatchRule from class to method annotation and fix review feedback