Consider adding top level domains to GUI configuration

Hi!

Mailcheck also has a setting for top level domain corrections. I found that having gmail.ch in the domain list was not enough for it to be given as a possible correction. I had to edit the jquerry.mailcheck.min.js and add the .ch domain to the list of top level domains. After this then gmail.ch was given as a possible correction.

Consider adding a top level domains GUI configuration to the module so people do not have to edit the .js file by hand.

God Bless!
Frederick