Added a note to the README re: installing an older version of simplejson.
Added a note to the README re: installing an older version of simplejson.

arlenesr28/pystache,arlenesr28/pystache,charbeljc/pystache,rismalrv/pystache,nitish116/pystache,jrnold/pystache,defunkt/pystache,jrnold/pystache,charbeljc/pystache,harsh00008/pystache,harsh00008/pystache,harsh00008/pystache,arlenesr28/pystache,beni55/pystache,rismalrv/pystache,rismalrv/pystache,nitish116/pystache,nitish116/pystache,beni55/pystache