Change airr variable names for alakazam style version

[ssnn]

• Go back to old names germline_alignment_COUNT and germline_alignment. Basically, revert commit 52cca7a, which is supposed to use airr column names
• User shorter names, alakazam-style: "id", "seq" and "germ" instead of "sequence_id", "sequence_alignment" and "germline_alignment".

[ssnn]

b41d790 and 5984f16