Update icons docs

[citizenmatt]

• [ ] XAML icons should be formatted to 16x16, 21x21 or 32x32, depending on usage. E.g. if the icon is supposed to be used in a code completion list, it looks like it's not scaled, and should be 16x16. Other usages (especially in WPF) can be scaled, so it's still worth using XAML
• [ ] XAML icons require ThemeColumns and RemoveBackgroundElement metadata.
• [ ] What should the default value of ThemeColumns be if there's only one icon? Color or -?

[citizenmatt]

This is a useful tool for resizing (and generally transforming) geometry paths used for icons:

http://blogs.msdn.com/b/gavingear/archive/2007/02/15/intoducing-pathmaker-a-tool-for-creating-path-markup-for-wpf-e.aspx

So your workflow can be SVG -> XAML via Inkscape, then hand edit the XAML to create a ResourceDictionary with a DrawingBrush containing a load of GeometryDrawing instances with Geometry paths from the converted SVG. This is likely to be the wrong size, so calculate a transform value to put you at 16x16, and use the tool to transform each path in turn.

[hypersw]

We're currently considering switching to SVG as the transport format, for various reasons. And it will be available as an additional input format. But this requires code for converting to Avalon at runtime which, considering how interoperability of vector formats generally goes, might get complicated. So there's no timeframe for this yet. If smb got ideas on which conversion code might be used (at runtime, so must be a decent license), you are welcome )

[hypersw]

There's some doc value in the MSBuild task xmldocs, e.g. considering answers to those columns questions. But unfortunately the nuget won't include xmldoc. I'll fix that.

[hypersw]

I've uploaded the new nuget to our internal server.