New helper object to controll dump file processing

* New class DumpProcessingController
* Updated existing examples to ue this class
* Extended test cases
Update release notes
Removed method to process recent dumps from WmfDumpFileManager

This is now covered by DumpProcessingController.
Mention breaking change in releae notes
Merge remote-tracking branch 'origin/master' into dump-processing-pipeline
Adopted example code to use new processing controller

(and fixed processing of property documents, which was missing)
Merge pull request #66 from Wikidata/dump-processing-pipeline

New helper object to control dump file processing
Change JSON serialization example to a generic serialization example

Currently, alternative code is commented out, but this can be useful
when the RDF serialization also works. Maybe this can turn into a
serialization script at some point.

The commit also fixes a typo in the last commit, due to which only one
daily dump was processed instead of all dumps.

In addition, two obsolete methods have been removed from JsonSerializer.
Remove dependencies to RDF package

RDF is not in master yet ...
Merge branch 'master' of https://github.com/Wikidata/Wikidata-Toolkit into create-parser-of-constraints