Warn about tags with value * (a literal star)

[Famlam]

If a key has the value of a *, probably someone took a validator output too literal.
I spotted this rule in the rules for TagWatchFrViPofm
name=* (a star) (to be replaced by fixme=*, lets talk about irony ;) )

That won't work in TagWatchFrViPofm, but we can probably add * (a literal star) to this spot:

osmose-backend/plugins/TagFix_BadValue.py

Lines 128 to 129 in 67f6ffa

	if tags[k] == "unknown":
	err.append({"class": 40613, "subclass": stablehash64(k), "text": T_("Concerns tag: `{0}`", '='.join([k, tags[k]])) })