About transparency

[Jasper Huijsmans]

> 
> BTW, if the amount of transparency could be set with a gui slidebar, it
> would be perfect for me. The current level of transparency is too opaque
> for my taste. Moving the slidebar to a full opacity would be equivalent
> to "=off". This of course, is out of the question for 4.2...
> 

Agreed.

I could even support that now in a 'hidden' config file 
(transparency=[1-100]).