sparql: Add sparql_connect built-in.
sparql: Add sparql_disconnect built-in.
sparql: Add sparql_query built-in.
sparql: Add test case, fix bugs in sparql_query, remove async mode.
sparql: Clean up.
sparql: Separate sparql_select and sparql_ask builtins.
ProvaSparqlQueryImpl: Return status value of sub class processQuery() implementation.
ProvaSparqlQueryImpl: Use AtomicInteger for queryid generation.
Revert "ProvaSparqlQueryImpl: Use AtomicInteger for queryid generation."

This reverts commit b609e022466a78b81336b54024f388b80a352d92.
ProvaSparqlQueryImpl: Use AtomicInteger for queryid generation.
Make the sparql built-ins optional (using Spring dep.inj. and maven profiles).
Add missing OpenRDF dependencies.
Merge branch 'master' into sparql-plugin-optional
Set version range for spring dependencies.
Merge pull request #4 from maltoe/sparql-plugin-optional

Spring-based SPARQL built-in.