Recreated fix from Blake on sessionless rexpro where serialization occurs in the same thread as the thread that mutated the graph.
Update changelog.
Merge remote-tracking branch 'origin/23fixed'

Conflicts:
	rexster-protocol/src/main/java/com/tinkerpop/rexster/protocol/filter/ScriptFilter.java
Merge remote-tracking branch 'origin/master' into available