Upgraded file handing to use filedescriptors
Upgraded sparql

* Fixed scalibility of graph level security
* Added RDF_INSERT_QUADS and RDF_DELETE_QUADS
  to optimize sparql:
	insert { graph `iri(?:param1)` {...} graph `iri(?:param2)` {...}
Added new BIF function sum_rank
Updated code generation

suppressing isiri_id(column) and similar checks if there's a good
equality between a column and some other expression that is known
to be iri_id
Updated codegen for literals with types and languages
Extended mp_check_tree to support circular structures in tree w/o hanging
Added ldp links to http headers for DAV
Added suppport for private sponge
Merged code from V7 branch
Fixed select where { service { select { }}} on a database with quad maps in use
Fixed typos