Default pattern for validateAddress()

[dregad]

I really like what you did with validateAddress() method selection in 5.2.7.

If I may make a suggestion, I think it would be better when $patternselect is not one of the accepted value, if the function fell back to auto instead of php.

(I had a case where I mistakenly passed null instead of auto and it took me some time to understand why user@localhost was rejected)