First version for SPARQLSelectRendererVisitor : only works with no linkkeys or with intersect simple linkkeys (have to complete with Equals linkkeys and composite linkkeys) 

- BasicOntologyNetwork now loads extensions

- replaced Jetty MulpiPart by Commons fileupload
- fixed file upload pretty bug
- implemented fileupload destruction

- added some Cell grammar

- fixed entity order

Modification of queries generation (on fr.inrialpes.exmo.align.impl.renderer.GraphPatternRendererVisitor) for using federated queries + first test for SPARQLSelectRendererVisitor

Fixing static vars to class var + getting hability to retrieve queries on GraphPatternRendererVisitor

- Reengineered

- Implemented always blank in construct