meta-rules: useless-ignore and invalid-ignore

[MarkusTeufelberger]

useless-ignore would fire if a certain line/task/... has a noqa comment added or if a file is explicitly on some ignore list even though ansible-lint would not find anything wrong there.

There are 2 parts to this, the "this noqa comment no longer actually applies" part would be the more useful/easier one to make sure that these comments only show up where they are actually relevant, the "you are explicitly ignoring files that are not problematic" one could be a bit too overreaching in case someone wants to make sure that also in the future ansible-lint doesn't look into certain places.

invalid-ignore would complain about comments that follow the noqa schema ansible-lint expects but that mention no rules it knows about. This is helpful to prevent/detect misspelings or tipos.