Add capture_stack() and some more reflection
rename Interpreter back to Stack. Final answer
rename make_interpreter
add Map.empty, rename make_interpreter to make_stack
add Stack.find_active_frame_for_term
add Map.get_optional and Map.map_element
Bug fix, unknown_functions were being 'fixed' and not reporting error
bug fix, migration didn't understand Mutable values
Various crash fixes in reflection api
add reflect:caller
move repeat() to kernel.cpp
add tests/actors/queue_sample.ca
add circa_inject_context
fix crash on Method Not Found error
add List.to_set
add Term.trace_dependents
bug fix with test_spy
add funcs including Term.set_value, fix bug in Frame.has_parent
add Rect.grow and fix closure crash