Windows support

These are a few changes to better support Windows.  We may want to add a warning to the documentation that we don't really want to support Windows, but are just including it as is.
Based on our discussion, I've added a warning to the documentation that we
don't support Windows and that the documentation is just for development,
and I've removed the Windows-specific capacity code in favor of just
returning None values.  This makes it so no capacity information is shown
on a Windows host, but at least it doesn't throw an error as it did before
the change.

If you think the documentation needs to be bolder yet, I'll have to figure
out how to do that in Sphinx.

On Wed, Sep 17, 2014 at 12:36 PM, Jeffrey Baumes <notifications@github.com>
wrote:

> In package.json:
>
> > @@ -29,6 +29,6 @@
> >      "jscs": "1.6.1"
> >    },
> >    "scripts": {
> > -    "postinstall": "./node_modules/.bin/grunt init && ./node_modules/.bin/grunt"
> > +    "postinstall": "grunt init && grunt"
>
> According to https://www.npmjs.org/doc/misc/npm-scripts.html (search for
> ENVIRONMENT), as long as grunt is a dependence in package.json, the local
> "grunt" will be available, in which case this change does not affect
> behavior at all - local grunt is still used. Not sure what happens if both
> local and global grunt are installed, but I would guess the local has
> precedence.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/girder/girder/pull/328/files#r17675758>.
>