Allow to more easily work with read results by putting them in a using statement to dispose their internal Stream
Expose the inner transaction
Adding support for WriteBatch.MultiAdd & WriteBatch.MultiDelete
Minor
Merge branch 'voron' of github.com:ayende/raven.voron into voron

Conflicts:
	Voron/Impl/SnapshotReader.cs
	Voron/Impl/TransactionMergingWriter.cs
	Voron/Impl/WriteBatch.cs