[development] Move multiple theme per site support to contrib module

[Adrian Simmons]

Adrian Rossouw wrote:
> How many people actually use user specified themes on their sites?
Not me, not 'users' as such anyway. I do use this functionality when making 
new themes though. The admin account gets it's theme set to a working theme, 
whilst anonymous and themedev users get the default 
new-theme-in-progres-which-might-be-broken.

It's not hard to come up with other uses either - suppose I want to test a 
new theme on a live site?

This is a good feature, I'm sure we'd get by without it, but...
Move it to a separate module? Maybe. To contrib? Everyone always fears a 
module moved there will languish.

Ditching global theme settings and moving to per theme only seems like a 
good simplifying idea though.

-- 
Adrian Simmons (aka adrinux) <http://adrinux.perlucida.com>
e-mail <mailto:adrinux at perlucida.com>