cruft shown in successful test run

[Curtis Hovey]

The test runnner passes bug there are several lines of cruft shown from either stdout or stderr. One case is from the Filtered reported which writes to the console during tests. Another case is because a signal is missing from a fake gedit object. The last issue relates to do_population in the c-object...this method was changed to work with testing -- extract the testable part to avoid the c-code.