New french population extractor

Add a new extractor for the french wikipedia dump
Create a new destination dataset

A new destination dataset has been created for the new french population extractor.
Code cleaning

- throw an exception if the dump analysed is not the french one
- remove the "hard" URIs creation by a more cleaner way
- remove the datatype because it was already precised with the dbpedia ontology
Remove a debug println
Merge pull request #46 from jplu/frenchPopulationExtractor

French population extractor