Invalid test cases in v2.1 w.r.t. Comment

[thbeu]

The following test cases in the release_2_1 branch violate the markup.xsd because of the missing Comment element inside Comment. Additionally, they do not seem proper elements of v2.1 at all due to legacy elements VerbalStatus, Status and Topic.

https://github.com/buildingSMART/BCF-XML/blob/d67e2a16425f4740182084bba4c937b1b36198c1/Test%20Cases/v2.1/Visualization/Single%20visible%20space/unzipped/a3befb7d-8395-4e52-bbca-382fc4198217/markup.bcf#L11-L17

https://github.com/buildingSMART/BCF-XML/blob/d67e2a16425f4740182084bba4c937b1b36198c1/Test%20Cases/v2.1/Visualization/Single%20visible%20wall/unzipped/d029895e-2bdc-4f48-8bf4-8e540425f238/markup.bcf#L12-L18

https://github.com/buildingSMART/BCF-XML/blob/d67e2a16425f4740182084bba4c937b1b36198c1/Test%20Cases/v2.1/Visualization/single%20invisible%20wall/Unzipped/e1fff3a6-db0f-48e8-a240-0e2f38b2fc21/markup.bcf#L11-L17

https://github.com/buildingSMART/BCF-XML/blob/d67e2a16425f4740182084bba4c937b1b36198c1/Test%20Cases/v2.1/Visualization/all%20components%20and%20spaces%20visible/unzipped/2c02d25f-6cb7-4c14-8737-9c340699d351/markup.bcf#L11-L17