Uc 44 Marketing email opt in

Adding marketing opt-in checkboxes to the facebook modal and the signup form.

The state of the checkbox is different depending on where the user is located. If they are in Canada, the checkbox is visible and unchecked. If they are in Europe, the checkbox is visible and checked. Anywhere else, the checkbox is hidden and checked. 
@armonr, not sure if you noticed that there are two separate methods being called: `getCountryCode` and `getContinentCode`.