[MetaCRS] add Didier Richard as committer for Proj4js

[Michael Adair]

I am proposing to add Didier as a commiter for Proj4js as he has 
supplied many good patches.  I'll take silence as agreement with this, 
so if you have any objections let us know.

As a committer to PROJ.4 already, I suspect he already has permission to 
do this, otherwise I'll need someone to add him to Proj4js directory of 
the svn.

Mike