These tests clear up a misunderstanding of mine: Monitoring
nonexisting files and directories *does* work with the inotify
implementation, it just has a very long timeout for scanning
for missing locations, so the test needs to take that into
account.
Add a new test which checks that atomically replacing a file that
is being monitored by GFileMonitor produced the expected events.
The test can easily be expanded to cover other file monitoring
scenarios.
