* Calling `Discourse.reset()` creates a new container
We should run our de-initializers only after acceptance tests,
since initializers are not run outside of acceptance tests anyway,
and the container at this point can be passed properly to the
`teardown()` method.
* Remove `Discourse.reset` from tests
This would cause a new container to be created which leaks many objects.
* `updateCurrentUser` is more accurate than `replaceCurrentUser`
* FEATURE: introduces minimum trust level for polls
This commit makes `poll_enabled` less misleading and introduces `poll_minimum_trust_level_to_create`. If poll are enabled they will always be cooked, and if you have the required trust level you can create polls. As a side effect, it also fixes a bug where rebaking a post created by staff member when `poll_enabled=false` would end up not cooking it.
It also adds more tests to ensure settings are respected.
* admins should be whitelisted
* checks for admin in post validation
* test for >= instead of == trust level
