Comment out an unneeded section now obviated by Jereoen's OpenCPU section.



git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rprotobuf@725 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Fix some typos / add misisng articles in Jereoen's new OpenCPU section.
Move this example before the MapReduce one.

It uses the serialize_pb method but we haven't described that here.  A
short introduction of that concept is needed for the application.

I think some of the first paragraph here should be moved to the
introduction so this section can focus only on an application.



git-svn-id: svn://svn.r-forge.r-project.org/svnroot/rprotobuf@726 edb9625f-4e0d-4859-8d74-9fd3b1da38cb