** demarcation of indented blocks
   :PROPERTIES:
   :DATE:     2011-09-04
   :END:
Demarcating a block with the point part-way in a line should indent
the remainder of the line in the second block.
    #+begin_src sh
      echo 1
      echo 2
      echo 3
      echo 4
    #+end_src

becomes

    #+begin_src sh :results silent :session something
      echo 1
      echo 2
      echo
    #+end_src
    
    #+begin_src sh :results silent :session something
           3
      echo 4
    #+end_src