Problem: zproject was generating zyre_prelude.h

Solution: fix zproject, and regenerate project here.
Problem: lagging behind zproject

Solution: generate project and store results.
Problem: minor flaws in comments

Solution: minor fixes to comments
Problem: poor style in zyre_test

Solution: delete ugly code. If it doesn't look right it doesn't
deserve to survive.
Problem: license.xml is not in obvious place

Solution: move to root directory.
Merge pull request #276 from hintjens/master

Problem: zproject was generating zyre_prelude.h