Added assert_empty, assert_not_empty, and tests
Changed assert_not_empty to use else on a for loop
Better error message for assert_empty

Also, cleaned up imports
Better assert_empty message; testing assert_empty's message; assert_raises_particular_exception and tests
add an event to report starting of a test case
let plugins modify test_runner too.
add sandbox violation collector plugin
use verbosity options in violation_collector plugin
cleanup
introduce ViolationCollector class
store violations in db and report syscall violations by count
threading is just tooo slow.
still can not use memory db. two different processes are using the same db.
violation collector plugin requires catbox with pcre
wrap around test program instead of runner to prevent test discovery failures.
revert previous and wrap test runner. discovery failure is not caused by that. looks like the bug is coming from http_reporter branch...
better reporting & adjust verbosity levels
slightly better reporting
Merge remote-tracking branch 'troscoe/troscoe_35978_exceptions_in_class_setup_teardown_http_reporter' into catbox
init reporters just before runner