This closes #77
tidies of Brooklyn node (warnings, logging)
promote snake-yaml dependency and Yamls utility to utils package, and use yaml parsing for map coercion to be much more flexible in terms of string-to-map coercion
remove dead code and tidy warnings in camp code
more tests for BrooklynNode, including test which uses REST API of local instance (and new "SameBrooklynNodeImpl" semi-mock); and adds BrooklynEntityMirror with test
support effector parameters which are maps (@sjcorbett just did this also; now this commit simply adds a test for this)
fix intermittent failing test by ensuring we wait for persistence to complete