Break dependency between state and apiserver/params package

This PR breaks the dependency between the `state` package and the `apiserver/params` package. 

Specifically the types that were imported by `state` from `apiserver/params` have been moved to a third package, the root of the repo. This is only a temporary measure to break the dependency, please don't get too hung up on the location of these types.

The plan from here is to move the relevant types into `state` if necessary, and relocate the others to the appropriate place.

This will also remove all the nasty functions that translate from constants in `state` like Life or Status to constants that were in `apiserver/params`
Nit: given that AnyJobNeedsState is in juju.go, this test should probably go in juju_test.go.