test: add expected output for edge cases. Still need to test and debug

test/conftest.py

test/expected_output/load_platform.SABjson

test/expected_output/many_following.SABjson

test/expected_output/many_preceding.SABjson

test/expected_output/many_start_sessions.SABjson

test/expected_output/zero_think_time.SABjson

test/test_expected_outputs.py

test/workload/load_platform.swf

test/workload/many_following.swf

test/workload/many_preceding.swf

test/workload/no_session.swf

test/workload/one_session_many_jobs.swf

test/workload/zero_think_time.swf