Extract abstract ListScheduler class

.gitignore

b_asic/__init__.py

b_asic/core_schedulers.py

b_asic/schedule.py

b_asic/scheduler.py

b_asic/signal_flow_graph.py

examples/fivepointwinograddft.py

examples/folding_example_with_architecture.py

examples/lwdfallpass.py

examples/secondorderdirectformiir.py

examples/secondorderdirectformiir_architecture.py

examples/thirdorderblwdf.py

examples/threepointwinograddft.py

test/fixtures/schedule.py

test/test_architecture.py

test/test_core_schedulers.py

test/test_schedule.py

test/test_scheduler_gui.py