pg_contrib default schema

Hi pg Hackers,

First I using PostgreSQL for four year now, and I would like to thank you
all for your work :)

I'm currently doing a study about the Open Source database.

So I'm testing some of the contrib modules like dblink, tsearch, admin81 and
I was using postgis a lot in a previous life.
All that module add internal fonctions to the database, some in pg_catalog
(and I personaly don't like to mix Internal fonction and contrib) others in
pg_default.

Do you think it's possible to create a default schema called pg_contrib, and
write a "contrib modules coding rules document" to put all functions / types
... in pg_contrib (to tidy a little all that things) ?

Thomas