Add option to do strict validation check

[RobbeCl]

I ran into a 'bug' where the system said the VAT number is valid, when it was actually not.

checkVAT('BE0740-509975', countries) return true, because the library automatically clears the special characters (https://github.com/se-panfilov/jsvat/blob/master/src/lib/jsvat.ts#L107)

Would it be possible to add an attribute that specifies if the client actually wants to remove those characters?

I don't mind submitting a PR, if you don't have the time to implement this.

Thanks for your library!

[zurabarata]

@se-panfilov
having the exact same issue! ☝️
checkVAT('DE124725-365', [germany]) strips the dash from the string and sees DE124725365 as a valid VAT ID.
The checkVAT function should not strip special characters from the vat-string by default.