updates Download page

[daenney]

Currently the Downloads page states that because OS X has a systemwide installation of an old Twisted and there's no safe way to upgrade users are stuck with the Twisted Apple provides.

However, if one would use virtualenv/virtualenvwrapper it's perfectly possible to use a newer version of Twisted:

mkvirtualenv --python=pyton2.6 --no-site-packages --distribute  virtualenvname
workon virtualenvname
pip install twisted

The only problem with this is that a py2app bundled application that requires a newer version of Twisted would need to be launched from within the virtualenv otherwise they'd be stuck on Twisted 8.2.0.

If people are using a newer python version, from MacPython or something like that, their path is changed and they can install Twisted from pypi without breaking anything.

[thijs]

I don't have rights to modify this page, exarkun does, so assigning to him.

[exarkun]

I edited the page. It now. suggests that even on OS X Twisted can be installed from source if desired.