Accept some new gTLD e-Mail addresses

by allowing longer TLDs (up to 63 characters, which is the DN maximum: https://tools.ietf.org/html/rfc1034):
"Each node has a label, which is zero to 63 octets in length."

For an up-to-date-length, see http://stackoverflow.com/a/22038535
Merge pull request #907 from Rillke/master

Accept some new gTLD e-Mail addresses