evolve: adapt to the new metadata storage
Metadata are not stored as a "list" of (key, value) tuple instead of a binary
blob.
This adapt to ef880e28e56a in Mercurial.
all: tutorials/tutorial.rst static/logo-evolve.ico
sphinx-build . ../html/
tutorials/tutorial.rst: tutorials/tutorial.t
python test2rst.py tutorials/
static/logo-evolve.ico: static/logo-evolve.svg
convert -resize 36x36 static/logo-evolve.svg static/logo-evolve.ico