Add support for .uk SLD verification in OpenSRS.

.uk slds, like .co.uk, will otherwise fail with an **INVALID_NUMBER_OF_DOTS_IN_NAME** error.

There is also an option **my_tld_not_strict** that seems to be used in conjunction in some places with the **check_name_dots** used here, e.g. in NAME.pm. Not sure what it does, and seems to work fine here without, so left it out.