performance boost for GRAPH_EDGES and GRAPH_NEIGHBORS
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel
do not open the logfile manager when checking the version

Conflicts:
	CHANGELOG
added test case "multi-collection"
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel
updated documentation
Merge remote-tracking branch 'origin/devel' into pregel
Merge branch 'pregel' of https://github.com/triAGENS/ArangoDB into pregel
added count vertices