suggestion: limit domains input array

[andrzej-woof]

I've bumped into an issue providing long list of domains to to getDnsRecords on OSX:

• when full cmd to be executed is somewhere between 568263 and 568443 characters long it fails with /bin/sh: /usr/bin/dig: Argument list too long
• for much longer list of arguments it fails with Error: spawn E2BIG

it's going to be of course system dependent value but maybe worth putting in some limits?
Suggestions:

• limit domains input to some arbitrary number (1k domains?) and reject with meaningful error message
• limit command string length and reject with meaningful error message
• implement chunking for larger arrays (with parallel resolve)