stepping down as the backend_ps maintainer

Hi John, in case it is not obvious from my inactivity: it

    > turns out that I have not enough time and energy to do
    > much for matplotlib's PostScript backend. Therefore I
    > would prefer not to be considered the backend maintainer
    > any more :frowning:

    > Of course I will continue to follow the matplotlib
    > development and will try to provide patches from time to
    > time.

Hi Jochen,

Sorry to see you go :frowning:

Thanks for all the hard work you've put into making the PS backend
compliant. We'll keep hammering away at it. Poke in every once in a
while to make sure we aren't mucking things up.

Again, thanks a lot, and thanks for bowing out officially so I know to
take over rather than just grumbling and pestering!