Use ActionT with custom exception type

Handling 'Error's manually will get tedious with more 'Error's and
increasingly complex monad burritos. Therefore we replace Scotty's
'ActionM' with 'type ActionE = ActionT Error IO', enabling the use of
Scotty's 'raise' with 'Error' values. 'Error's are now directly
integrated with Scotty's error handling system instead of being handled
manually.

Import from Web.Scotty.Trans to get functions that use 'ActionT' rather
than 'ActionM'.

Require wai and warp packages for new type signatures.

Remove 'jsonHandler' as it's replaced by 'ScottyError' integration and
'jsonError'.

Rename Output.hs to Spock.hs due to its widened scope.

Signed-off-by: Stian Ellingsen    <stian@plaimi.net>
Signed-off-by: Alexander Berntsen <alexander@plaimi.net>
Reviewed-by:   Alexander Berntsen <alexander@plaimi.net>