Snapshot, legend cache started.
Find original legend in same WAL file if needed.
Fix bug with the size counting.
Add some explanations.
Merge branch 'maxmh' into devel

Conflicts:
	arangod/VocBase/document-collection.cpp
fix compile warnings for Visual Studio
fixed statistics interval
initial check in
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
disabled non-deterministic test
Fix behaviour of tests when few requests are done.
Merge branch 'devel' of ssh://github.com/triAGENS/ArangoDB into devel
speed up test cases
Basic implementation.