Added zone management pages

Fixes #13
Fixed Tree click method

self._root_element.click() didn't work for me, replaced self.root.click()
which seems to work fine.
Merge pull request #41 from jprovaznik/zone1

Zones management
added policy actions and events, basic unit tests
fixture-ize tests
trimmed list of events/actions
Merge pull request #40 from aweiteka/policy_events_actions

added policy actions and events, basic unit tests