.cabal: added a note about the hashmap package
.cabal: added a note about the hashmap package

Ignore-this: ac7597d9bef645c59fe5c1a4eb93db4c

darcs-hash:93986af153eed61a3b4129a0efb8b14f70b4d667

unhammer/bytestring-trie-0.2.4