0.2.0

Breaking changes

changed return value - now it returns upserted item(s)
deleted mapper option - use mapInsert option instead

New features

added options callbacks
- mapInsert(data)
- mapUpdate(data)
- mapUpsert(data, isNew)
- afterInsert(item, data)
- afterUpdate(item, data)
- afterUpsert(item, data, isNew)

Other

"main" field in package.json now points to unminified version of distributable script
Updated README.md