articles get default category "nofeed"

nofeed articles are excluded from news feed
Merge pull request #16 from mrterry/copyediting

Copyediting
Merge pull request #17 from mrterry/nofeed

articles get default category "nofeed"
add images for pythonxy and sage
better phrasing for associated projects
removed empty projects-2.rst
move john hunter memorial page to NumFOCUS news
move python_in_science to News
remove TODO.  we have github issues now
tweak image sizes