Build requirements:

  1. The "base64" utility from GNU coreutils.
  2. The "scour" SVG optimizer.
  3. The "fontforge" program.
  4. The "xsltproc" program from libxslt.

To run the test suite, you'll also need the "tidy-html5" program.

SVG Tricks:

1. To remove a "transform" from a group (like the bus) that was
   resized together, simply ungroup and regroup the whole thing.