New approach in semanticLayer

Started implementing tree structure.
Merge remote-tracking branch 'origin/feature/db-selection' into feature/semanticLayer

Conflicts:
	src/com/etk/data/DataSource.java
defined queryResult interface
New implementation of sparql queries

It's late, no idea what to write...
Merge remote-tracking branch 'origin' into feature/semanticLayer
Merge branch 'feature/semanticLayer' into feature/db-selection
Fix for RemoteSourceRDF, now it can be compiled
disi
Merge branch 'feature/semanticLayer' of https://github.com/ilucin/relsem-bridge-backend into feature/db-selection
demoable query executor