Added older VISA length. Source: http://en.wikipedia.org/wiki/Bank_card_number and http://www.regular-expressions.info/creditcard.html
Added cases to Diners Intl. Sources: http://en.wikipedia.org/wiki/Bank_card_number and http://www.regular-expressions.info/creditcard.html
"Laser cards stopped being accepted as of February 2014." Source: http://www.ipso.ie/section/LaserCardServicesLtd
Clean up + new case. Source: http://en.wikipedia.org/wiki/Bank_card_number
Added Dankort. Source: http://en.wikipedia.org/wiki/Bank_card_number
New Maestro cases. Source: http://en.wikipedia.org/wiki/Bank_card_number
Alphabetic order
Added InterPayment. Source: http://en.wikipedia.org/wiki/Bank_card_number
Added Diners Club US & Canada. Source: http://en.wikipedia.org/wiki/Bank_card_number
Added China UnionPay. Source: http://en.wikipedia.org/wiki/Bank_card_number