Code review comment for lp:~leonardr/lazr.restful/mutators-are-not-named-operations

This branch stops mutator methods from being published as named operations. To preserve backwards compatibility, users are allowed to specify in which version of the web service the change takes effect.

The tests in webservice-declarations.txt and the new example/multiversion/tests/operation.txt should explain the feature. webservice-declarations.txt also walks you through one place where the feature might cause someone pain (it's very unlikely, and difficult to fix, so I left it alone).