Add the whois package to the dependencies

[iaeiou]

Hi there,

if you get the following error:

./domain-check-2.sh: line 303: -h: command not found

you may need to install whois

apt install whois

@click0 , the same error appears with the fork you maintain, could you please add a line to the doc?

What about allowing issue submission directly to your fork? (I'm not familiar with Github but it seems to be possible: https://stackoverflow.com/a/16406283)

[click0]

There is already a mention of this in the script.
https://github.com/click0/domain-check-2/blob/23d7be38301bb25023fde0d74a358e20d7bc5b7c/domain-check-2.sh#L248-L249

[click0]

Fixed checking on the existence of binary files of the necessary programs for the script to work.
click0@2434d9f

[iaeiou]

I gave a try with the last version and mail (provided by the package mailutils in Debian) is required