Added additional log to Extractors
Merge branch 'master' of https://github.com/mff-uk/intlib.git

Conflicts:
	module/RDF_extractor/src/main/java/cz/cuni/mff/xrg/odcs/extractor/rdf/RDFExtractor.java
Merge branch 'master' of https://github.com/mff-uk/intlib.git
When changing state from Cancelling to Cancelled after backend restart
the context is deleted