Add `Module` type
Remove `withGhc` and `withGhc'`, they're not used anymore.
Add functions for dealing with packages, modules and bindings to GHCApi
Move DynFlag related functions from GHCApi to another module
Move `initializeFlagsWithCradle` to Monad.hs
Merge pull request #287 from DanielG/dev-untangle

Untangle Monad.hs and GHCApi.hs and some other changes