Log phase transitions (draft->public) Ensure phase transitions are logged in the mercurial-server.log file

Add support for phases This adds a "publish" permission level (between "init" and "write") required to be able to change the phase of a changeset from "draft" to "public". Update documentation accordingly. This is meant to be used for using the changeset evolution feature of mercurial, see http://evolution.experimentalworks.net/doc/

[test] add unit tests for ruleset We extract the rules building logic from readfile into a Ruleset.buildrules() method to ease testing.

Adding branch for phases