[202] Normalize SVG icons as 16px and cleanup
This commits improve on the previous state by:
- normalizing all the SVG icons as 16px width and height to avoid browser scaling
- normalize primary edge sizes at 1px width
- reposition and rescale the content based on the gif
- cleanup the resulting SVG with svgo
- document this process into README.adoc
Bug: #202 (closed) Signed-off-by: Cedric Brun cedric.brun@obeo.fr