Removed unused imports.
Merge branch 'master' of github.com:AKSW/SPARQL2NL

Conflicts:
	src/main/java/org/aksw/sparql2nl/naturallanguagegeneration/FilterExpressionConverter.java
Merge branch 'master' of github.com:AKSW/SPARQL2NL
Merge branch 'master' of github.com:AKSW/SPARQL2NL
Added multihreaded version.
Resolved-