Parse delimited from test

Hi, I need to parse multiple messages from one file. In Google protocol buffers I used [parseDelimetedFrom](https://developers.google.com/protocol-buffers/docs/reference/java/com/google/protobuf/AbstractParser#parseDelimitedFrom(java.io.InputStream)). This is my attempt to implement same method wire-way.
I think you should remove the `public` modifier from this. There's no need for it to be in the public API.