started improved SPARQL implementation
Merge branch 'develop' of https://git-wip-us.apache.org/repos/asf/marmotta into sparql

Conflicts:
	libraries/kiwi/kiwi-sparql/src/main/java/org/apache/marmotta/kiwi/sparql/persistence/KiWiSparqlConnection.java
towards SPARQL native
library updates (Sesame, Guava, ...)
adapt to API changes in Guava
fix MARMOTTA-367 (OPTIONAL support) and MARMOTTA-494 (SPARQL builder)
implement support for ORDER BY (MARMOTTA-496)