[dm-constraints] pulling in coryodaniel's changes
[dm-constraints] pulling in coryodaniel's changes

A lot of clean up work will probably have to be done in the specs. One of the puled in commits contained a change in another dm-more gem, dm-is-remixable. I attempted to leave that file (remixable.rb) untouched.

Support for M:M relationships in DM Constraint

datamapper/dm-is-remixable