Show which offsets were chosen in log?

[mschubert]

(I've got a couple of small suggestions that would help me interpret and diagnose how guide-counter is running. I'll post them here as separate issues, please feel free to ignore/answer very slowly.)

When I run guide-counter with offset detection and --offset-min-fraction, the terminal log displays how many counts it finds at each position:

INFO In "/path/to/my.fastq.gz" examined 100000 reads for guide start position and matched 87811 (0.8781).
INFO my.fastq.gz read offsets: 0->86047, 1->11, 2->7, 3->11, 4->11, 5->8, 6->5, (etc, until position 58)

Would it be possible to add/modify a log entry that states which offsets passed the threshold? e.g.:

INFO my.fastq.gz X of Y possible read offsets chosen: 0, M, N