Ritvik1712

In response to [issue#115](https://github.com/lambdamusic/Ontospy/issues/115), we are adding few additional complex test cases that address various aspects of SPARQL.

We tried to run SPARQL queries by copying them as it is from the demo [link](https://www.dbpedia.org/resources/sparql/). However we faced errors while running the queries due to lack of support for...