Add misbehavior tests

(Currently contains !499 (merged))

This MR adds some tests for extractor misbehavior:

• Unexpected exit (also e.g. crashes)
• Stalled extraction
• Modules succeeding but returning no data
• Modules not succeeding, but not providing an error
• Modules inserting wrong RDF data

And some more to check that potentially malicious behavior is intercepted:

• DBus access (extends to any local socket)
• Network access
• Fork and execution
• Filesystem write
• Filesystem read in disallowed locations
• Attempts to truncate files