This change adds a createComponents() method to Plugin implementations
which they can use to return already constructed componenents/services.
Eventually this should be just services ("components" don't really do
anything), but for now it allows any object so that preconstructed
instances by plugins can still be bound to guice. Over time we should
add basic services as arguments to this method, but for now I have left
it empty so as to not presume what is a necessary service.
this commit moves the most of the http related integ tests out into it's own
`qa/smoke-test-http` project where most of the test can run against the external cluster.