incgen: Fix init and reset stubs for events.
incgen: Fix init and reset stubs for events.

* da/compiler/incgen.py:

  -(gen_reset_stub): New function, generate a stub that clears event histories
   for a given process.

  -(gen_init_event_stub): New function, generate an initialization stub for a
   given event.

  -(gen_inc_module): Inject reset and init stubs to the inc module output.

  -(StubcallGenerator.visit_ResetStmt): Call reset stub for events that are
   query parameters, then call .clear() for remaining events.

mayli/DistAlgo,sghosh1991/distalgo,mayli/DistAlgo,sghosh1991/distalgo