Mudblood.Trigger: Removed 'guardT'

Since TriggerM is an instance of MonadPlus, this is already provided
with 'guard'.
Control.Trigger.Monad: Added (<||>)

a <||> b returns a trigger functions that first tries to apply the first
trigger. If that fails it tries the second.
Mudblood.Trigger: Generalize 'guard*' and 'on' functions to arbitrary
monads.
Control.Trigger: Introduce stateful triggers.
Mudblood.Core: Make stateful triggers an instance of MBMonad.
Some cleanup of Mudblood.Text
Mudblood.Text: Added Color <-> String conversion for DefaultColor.
Added module Mudblood.Contrib.ColorConfig

This module reads a color configuration from a file.
Moved regex stuff from Mudblood.Text to Mudblood.Contrib.Regex
Control.Trigger.Flow: Cleanup

- Removed commented out stuff.
- Removed parallel triggers, which never really made sense.