add_item_to_metafile() now takes a key so it can be used elsewhere
the use of exists() in add_item_to_metafile() now correctly calls a callback rather than expecting a bool
bump to v0.6.1 with filepath fix from #strk
fixup travis
Merge pull request #108 from dboze/fix-metafile-idempotence

Fix metafile idempotence
fix #109
merge
fix typo
clarify usage of existsAsync and better debug output around failed reading of metafile
bump to v0.6.2 with metafile fix
bump to v0.6.3 with new millstone.drainPool - refs #110 and mapbox/carto#301
Actually get #80 working
update changelog
bump to v0.6.4 with zipfile double unzip fix
upgrade to latest node-srs - refs https://github.com/springmeyer/node-srs/issues/28
bump to v0.6.5
updated unzipping to use file streaming to get around node buffer constraints