exact values in file size filter

[Rogach]

Currently fd --size 0b gives an error: [fd error]: '0b' is not a valid size constraint.

Documentation seems to require + or - prefixes (greater than or less than). Maybe we should handle cases without prefix as meaning "this exact size"? find does it this way - --size 0 will find files with size of zero bytes.

(if such change is acceptable, I would be willing to provide a pull request)

[sharkdp]

That sounds great, yes! Thank you.

This also looks good if used with --size=<value> syntax:

fd --size=100b

[sharkdp]

released in v8.2.0.