Check if we can use the sequence description for the id

[Jason Vander Heiden]

Need to check that we can use the full header of a sequence (description) of a Seq object instead of the id attribute as the id. If so, we should change the behavior of everything to avoid wonky behavior with spaces, particularly in the case of ConvertHeaders-imgt. "Homo sapiens" can mess things up, by causing the duplicate keys.

[Jason Vander Heiden]

Fixed ConvertHeaders-imgt awhile ago. More broadly, we should leave header parsing as is, because it's working and we might need to swap the entire interface out for something faster.