Add terminal progress output for best match

[danielmarrama]

The best match feature can take a long time especially if >1000 peptides and the proteome is large. It would be useful to output to the terminal the progress for the user.

Example:

Searching 1,000 peptides for best match using k=15.
Found 4 peptide matches with 0 mismatches.
Searching 996 peptides for best match using k=7.
Found 67 peptide matches with 1 mismatch.
Searching 929 peptides for best match using k=3.
Found 245 peptide matches with 2 mismatches.
Found 501 peptide matches with 3 mismatches.
Searching 929 peptides for best match using k=2.
Found 183 peptide matches with 4 mismatches.
Done.