(#51) Updated to support setting the volume state value. 
Also made a few tweaks to fix #50, and tidied some of the logging.
(#51) Slight tweak to allow for setting state on new resource creation.
(#51) Further refinement to volume state handling.
Merge pull request #53 from fatmcgav/master

Merge #50 and #51 onto v0.4-fixes