Improve header consistency for better machine parsing

[valentynbez]

Example headers:

# motus version 3.0.3 | merge 3.0.3 | info merged profiles: # git tag version 3.0.3 |  motus version 3.0.3 | map_tax 3.0.3 | gene database: nr3.0.3 | calc_mgc 3.0.3 -y insert.scaled_counts -l 75 | calc_motu 3.0.3 -k mOTU -C no_CAMI -g 3 -c | taxonomy: ref_mOTU_3.0.3 meta_mOTU_3.0.3 
# call: python /nfs/cds-peta/exports/biol_micro_cds_gr_sunagawa/scratch/vbezshapkin/conda-envs/qiime2/bin/motus merge -i A.motus,B.motus -o paired-end.motus

• Additional # in the first line before git tag should be removed
• Separators are different on both lines (mix of :, `,|&_`), and it would be convenient to parse version info + call command and params simultaneously.