Merge pull request #27 from stanislasrybak/master

Add final changes installation.mako.
Correct headings closing tags.
Add SVG + Ractive waterfall (with no SVG library).
Improve comment.
Allow to open and close waterfall columns using a tree of variables.
Add link to variables definitions.
Improve SVG scaling.
Improve waterfall layout.
Handle clicks on bars.
Add changes to installation.mako, add exemples to exemples.mako (decomposition and waterfall)