initial draft
build full WriteBatch in v8 thread
Merge branch 'gruber-inspired-batch-optimisation' into 0.2-wip
Merge remote-tracking branch 'origin/chained-batch' into 0.2-wip

Conflicts:
	binding.gyp
	src/database.cc
(uv_after_work_cb) cast in cbatch for Node 0.10