create an `:mb-run-mode` config property which defaults to "prod" and add couple predicate functions in our config ns for checking `is-prod?` and `is-test?`.  then update our event listener startup calls and wrap them with `(when (config/is-prod?) ...)` so that we only start them up when we intend to run the app for real.  lastly, update our environment for our expectations unit tests so that :mb-run-mode is "test" and thus our event processing listeners are not started for unit tests.

add Stencil to clojure libs so that we can have a very simple library for doing mustache style templating.

ordering. Fix lint error

metabase.driver.mongo.util namespaces

generic SQL will share it.
Add Mongo lib dependency