Add zero alignment output

[esteinig]

No description provided.

[codecov]

Codecov Report

Merging #24 (33603d5) into main (3dfe52f) will decrease coverage by 2.08%.
Report is 12 commits behind head on main.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main      #24      +/-   ##
==========================================
- Coverage   24.23%   22.15%   -2.08%     
==========================================
  Files           5        5              
  Lines         388      429      +41     
==========================================
+ Hits           94       95       +1     
- Misses        294      334      +40     

Files	Coverage Δ
src/cli.rs	60.00% <0.00%> (+5.46%)	⬆️
src/utils.rs	0.00% <0.00%> (ø)
src/align.rs	9.24% <0.00%> (-1.38%)	⬇️

... and 1 file with indirect coverage changes

[esteinig]

• add zero alignment output with --zero flag - when supplying a reference .fasta references without alignments are output in the table
• if a grouped reference is selected, the default output table contains the coverage information of the selected references for each group instead of the grouped output data, this can now be output with an optional --group-data <FILE> command line option