0.04 2012-07-15

   - #78102: Fix the 'options' and 'type' constraints [George Hartzell]
     They previously did not call fail_constraint, and thus never actually
     failed.
   - #77654: Allow 'required' constraint on leafs to pass with '0'.

0.03 2011-02-04

   - Added the 'type' constraint which allows you to use a Moose type
   - leaf($foo) sugar is now sugar for leaf(constraints => [ type($foo) ])