use CFRunLoop directly in `ipython kernel --pylab osx` via matplotlib.backend_macosx.TimerMac, rather than Tk Fallback on Tk if matplotlib is < 1.1.0, which introduces the necessary Timer. This means that it still won't work on current EPD, which has X11-linked libtk and matplotlib 1.0.1, but at least it will display a warning explaining why. also remove caveat in docs that qtconsole doesn't work with native MacOSX, since it does on normal (non-EPD) installs. So this will work in more places, but still not in most common failure case (stock EPD) described in #640.