- Upgraded some pom descriptions

- corrected Relation/PropertyId equals/hashCode

- modified parsers accordingly
- all implementation uses relationType to create cell relations
- genericised read/write and SWLCache for relations
- added interface for Disjunctive and Algebra relation
- added BitSet-based implementation of disjunctive and algebra relations
- developed A2 and A5 relation algebra
- extended AlgTest tests
- added V5 comment tag to anticipate API modification

Adding new tests : SPARQLSelectRendererVisitorTest.QueryFromAndProperty + SPARQLConstructVisitorTest.ConstructFromAndProperty. Have to uncomment and fix

- improved server layout and functioning

- BasicOntologyNetwork now loads extensions

- all logging through slf4j
- all command-line parameters through commons cli, duly tested

- forced edoal:Datatype in edoal:datatype

- Fixed a bug in the EDOAL parser and printer for taking into account the edoal:type within edoal:Literal

- implemented Relation cache in BasicRelation

- added more tests in parser

- Implemented transformations

- reengineered ValueExpression hierarchy and treatment
- first set of systematic tests