Editor's Guide for new volunteers

Hi, Julee, Scott.

Just going over this before the sprint, and noticed that we still point
people to http://docs.webplatform.org/wiki/WPD:Most_Wanted_Tasks (which is
obsolete, I believe) from
http://docs.webplatform.org/wiki/WPD:Editors_Guide/step_3_become_familiar_with_the_wiki
.

Both the Editor's Guide and Getting Started point to each other for where
to go first for how to get going quickly.

After Scott's careful arguments about why the long, consolidated Getting
Started page is good, the Editor's Guide seems overly fragmented.

It was still hard to find css stuff to work on.  Most of the stuff listed
on Getting Started is from apis, except for code samples, and a couple of
articles flagged for grammar.

DougM