PromoCampaign: make location_str property.
Add location to PromotedLinkTraffic table.
Use constant_time_compare for checking webhook secrets.
Add 'expired' noop event for CoinbaseController.
Fix ValidCard validator.
Fix "-->" appearing in IE<8 due to conditional comment syntax.
CSS Filter: Add some more properties.

https://developer.mozilla.org/en-US/docs/Web/CSS/pointer-events

https://developer.mozilla.org/en-US/docs/Web/CSS/image-rendering
https://developer.mozilla.org/en-US/docs/Web/CSS/image-resolution
https://developer.mozilla.org/en-US/docs/Web/CSS/image-orientation

http://www.w3.org/TR/css3-grid-layout/