Added wikibase extension type

Change-Id: Ie6e18a4be7991935ce1063cd86b667857a2b669f
Rename some renaming things from Query to QueryEngine in QueryEngine component

Change-Id: I15c600d69e1c4be474533950b62094c54ef4100d
Merge "Added wikibase extension type"
Merge "Rename some renaming things from Query to QueryEngine in QueryEngine component"