make TSV output default

Key Updates

1. Output File Handling:

   • The --tsv flag has been deprecated. TSV output is now the default format.
   • If input is name fp rp, adding support for other output formats.
   • For both mfeprimer and mfeprimer spec, results will be saved as out.spec.tsv.
   • Additional outputs for mfeprimer:
     • Dimer analysis: out.dimer.tsv;
     • Hairpin analysis: out.hairpin.tsv.

2. Bug Fixes:​

   • Resolved issue #26;
   • Mismatch not working in tsv mode;

3. Sub-command Enhancements:​​

   • New sub-commands are now available:
     • mfeprimer search: homology search for short sequences like primers against genome database, require pre-indexed by mfeprimer index;
     • mfeprimer degen: convert a DNA sequence from ambiguous (with degenerate bases) to unambiguous DNA list;
     • mfeprimer split-fasta: split fasta into N parts with almost equal size;
     • mfeprimer thermo: thermodynamics calculation for oligos.