Massive refactoring around the Action monad

[np]

• Add aliases for common constraints:
  • type MonadThentosIO m = MonadLIO DCLabel m
  • type MonadThentosError e m = MonadError (ThentosError e) m
  • type MonadThentosReader m = MonadReader ActionState m
  • type MonadQuery e m = (MonadThentosReader m, MonadThentosError e m, MonadThentosIO m)
  • type MonadAction e s m = (MonadThentosReader m, MonadThentosError e m, MonadState s m, MonadThentosIO m)
  • type MonadThentosFError m = MonadThentosError FActionError m
  • type MonadThentosFState m = MonadState FrontendSessionData m
  • type MonadFAction m = MonadAction FActionError FrontendSessionData m
• New module Thentos.Action.TCB for actions which are unsafely built and trusted to be safe to use.
• Remove UnsafeAction and unsafeAction all these unsafe calls are made through liftLIO . ioTCB.
• Rename one getConfig to readConfig as this one is reading the configuration file.
• Abstract away most of the use of the Action monad.
• Rename the Action monad to ActionStack which helps to track the few occurrences left.
• Add a monad parameter to ProxyAdapter for the corresponding action monad.
• Add extendClearanceOnThentosAuthCredentials which is doing the check of privileged IPs.

[Mikolaj]

Even given my limited understanding of Thentos, the diff makes sense and overall LGTM.

[fisx]

I finally read through this. Like!

[np]

Thanks for the review @fisx !