Add custom checker for Password values We override the default converter to pass Binary values through, but don't do anything about the checker. This worked previously because yams allowed StringIO instances, although its converter didn't do the right thing for them. Fixing this in yams requires that we properly register a checker.

[component] give Links a __repr__

[debian] move markdown dependency from cubicweb-web to cubicweb-common Pointed out by David Douard.