[TEST] Built a JavaScript interface to navigate through nodes as a hierarchy

[TEST] tried to do something useful with "dc.js"

[GIT] Added a patch for cte_tree in init/cte_tree.models.diff

(see init/post-install-fixes.README for more details)

(could not access CTE methods such as .descendants(), etc.)

NgramsCache: ngrams are now stored in lowercase

[FEATURE] Added a RESTful URL : /api/corpus/95/data?mesured=ngrams.count&parameters[]=metadata.publication_year&filters[]=ngram.terms|bees

[FEATURE] Resources - Now the digest is computed for every added resource, and duplicates are not appended to nodes