interpreter + forkify fixes

hercules_ir/src/ir.rs

hercules_opt/src/fork_guard_elim.rs

hercules_opt/src/fork_transforms.rs

hercules_opt/src/forkify.rs

hercules_opt/src/ivar.rs

hercules_test/hercules_interpreter/src/interpreter.rs

hercules_test/hercules_tests/matmul.hbin

hercules_test/hercules_tests/out.hbin

hercules_test/hercules_tests/save_me.hbin

hercules_test/hercules_tests/tests/forkify_tests.rs

hercules_test/hercules_tests/tests/loop_tests.rs

juno_scheduler/src/compile.rs

juno_scheduler/src/ir.rs

juno_scheduler/src/pm.rs