added documentation for KEEP
less plans created by optimizer
updated CHANGELOG
added test for mergeObjects
removed duplicate entry
fixed issue: #1083
optimizations
implemented LENGTH in C++
removed unused mr-actions directory
Fix typo and add '_key' attribute description.
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel
fixed cursor ttl issue

Conflicts:
	CHANGELOG
Merge pull request #1158 from yojimbo87/devel

Fix typo and add '_key' attribute description.
fixed precedence of range operator
fixed range operator precedence
Fixed #1007 spelling error fixed
include or exclude system collections from replication
Merge branch 'devel' of https://github.com/triAGENS/ArangoDB into devel
fixed some compile issues
move to EOL before executing command