key/class/id support about remark-attr

[arobase-che]

Hi,
key should work. But class and id interfere with the notation .class and #id.

They is no obvious solution for the support of class and id attributes. But it may be improved.

[arobase-che]

Ok so, now, class and id can be used. If it interferes with the notation .class or #id, the first to appear win.

So .class1 class=class2 is .class1
class=class1 .class2 is .class1 .class2
id=id .notit is id
.notid id=id is notid

It was a md-attr-parser problem btw.