Unit tests depend on presence of file outside of repo

The hyperloglog unit tests depend on the presence of /usr/share/dict/words (see https://github.com/tylertreat/BoomFilters/blob/611b3dbe80e85df3a0a10a43997d4d5784e86245/hyperloglog_test.go#L34).  It would be helpful to include the test data in the repo to ensure the tests work without modification on systems that don't follow that dictionary path convention or don't load a dictionary package.