[Mono-winforms-list] Remove horrible MONO_MWF_USE_CARBON_BACKEND env vars

[Geoff Norton]

Miguel,

On 22-Jan-08, at 4:16 PM, Miguel de Icaza wrote:

>
>> We could possible provide a env override to force back to X11 on the
>> mac, but since we dont work on 10.5 anyways (x11) I'm not sure how
>> much value there is in this.
>
> Supporting X might come in handy when we do designer integration into
> MD.

The updated patch I sent after this one includes a settable variable  
to force back to X support.

-g