load-in2-count: Add json/TSV machine readable info

This changes the CLI flag that enables machine readable info so that to
enalbe this behaviour, you give it an argument of either 'json' or
'tsv'. This allows for a user choice of a versioned, dat-friendly json
or something easy to whack into R and plot.
Add format version to load-in2-counting json info

Add a file format version key-val pair