Attean SPARQL triple store

 AtteanX::Store::SPARQL implements a simple immutable triple store,
 which simply allows programmers to use Attean facilities to query
 remote SPARQL endpoints.
 .
 This distribution also brings a corresponding AtteanX::Model::SPARQL,
 which allows query plans to be made, and an
 AtteanX::Store::SPARQL::Plan::BGP plan class, which contains a
 rudimentary cost estimate that attempts to avoid sending Cartesian
 joins to remote endpoints if possible.
 .
 SPARQL is an RDF query language, that is, a semantic query language for
 databases, able to retrieve and manipulate data stored in Resource
 Description Framework format.
 .
 Resource Description Framework (RDF) is a standard model for data
 interchange on the Web.