R2RML: publishing the second draft

Latest Editors' draft (v 1.42): http://www.w3.org/2001/sw/rdb2rdf/r2rml/

Worked on the R2RML document to address the following issues to make it 
ready for publishing:

    * Issue-22: added note to Sec 1.3
    * Issue-24: changed "child." to "{child.}" and added a note about
      allowing complex join conditons.
    * Issue-26: added rr:unnamedGraph IRI as a possible value for
      rr:graph property to indicate that the generated triples should be
      stored in the unnamed graph (besides storing them into specified
      named graphs, if any).
    * Issue-31: Changed "blank node label" to "blank node identifier"

Issues to be addressed:

    * Figures need to be consistent with the current text. (Boris, could
      you please upload the latest figures or send us the pointers.)
    * Issue-28: Needs a test case. (Boris, could you please add a test
      case.)
    * Issue-29: Eric is going to write a note.
    * Issue-30: Richard is going to write a note.

Thanks,
- Souri & Seema.