Add unbuffered option (bufferChunks, default true) and a single test.
Need to do unbuffered version of all tests.
Rename option to unbuffered and add properties to tests
Split up tests into buffered and unbuffered and add more unbuffered tests
Finish unbuffered tests and add docs
Don't name transform function as not recursing any more
Merge pull request #1 from davedoesdev/unbuffered

Add option to return message parts as they arrive