Changed stream type and size to to deal with larger requests

The current library fails during json serialization if the size of  the objects being pushed
to the database is to large/to many.

We changed the stream from being a PipedInputStream to a byte array stream and increased
the size of the buffer to more fit our needs.

The size should be configurable (make it a constant is probably enough) but we didn't want to make
to large change.