Automate Icon Creation

[mfranzke]

          Before you merge this: Should we make this an automated step? (The transform of the original SVG files)

Originally posted by @shartte in #267 (comment)

[shartte]

I can look into this, we've had a similar workflow in a previous project, which - i think - actually made pretty much the same changes to the original icon sources.

[mfranzke]

@shartte no pressure on this one, we'll have an automated process and new tools for the new version; so we'll be more than happy if you could contribute, but it would even be fine if you can't.