Make chainable batch extendable
Export AbstractChainedBatch from abstract-leveldown
[fix] Always return this from .put(), .del() and .clear()
Add AbstractChainedBatch extendability tests
README.md: Add text about _chainedBatch & AbstractChainedBatch
typo
small fixes
fix: Call ._write with correct arguments
fix: Fix tests so that they are runnable
Merge pull request #11 from rvagg/extend-chained

Make abstract-chained-batch extendable