ensure dissoc preserves meta
don't replace keys

fix #3

when associng on a key that's already present, the new key could still have a
different meta value than the existing key. In this case, we want to keep the
existing key and its meta value
equals does not need to check MapEquivalence

only equiv needs to do that
Merge pull request #2 from MichaelBlume/preserve-meta

ensure dissoc preserves meta
Merge pull request #4 from MichaelBlume/no-replace-key

don't replace keys
Merge pull request #5 from MichaelBlume/no-mapequivalence-in-equals

equals does not need to check MapEquivalence
generate collections using prep-tasks

runs prior to any other lein tasks
remove collections from repo

lein auto-generates them