support for "shard -> node" mapping change at runtime.
typo
Merge branch 'origin/master'

Conflicts:
	nrv-core/src/main/scala/com/wajam/nrv/cluster/DynamicClusterManager.scala
post code review fixes
after years of R&D, the tests now pass sucessfully.
added {}, just for you Alex
better exception
removed spaces
name clarified
fixed a bug fix that was supposed to be fixed but that I unfixed
also added tests.
Merge pull request #174 from wajam/jn-shard-move-support

support for "shard -> node" mapping change at runtime.