added CC 4.0 SA license

The dogecoin.com website is not officially open sourced and therefore making and submitting changes to the site via github technically wouldn't be allowed and the owners could take legal action against those making improvements to the site.  I have brought up this issue twice, but nobody has responded.  Perhaps a better way is to simply create a pull request to open source the site and you can decide to merge it or not.

@ummjackson @langerhans @PowerLemons This is an important issue that has been ignored for a while now.  It's imperative that you as the legal owners of this site address this issue explicitly.

The reason being that as a contributor to dogecoin.com (internationalization code), I do not want to suddenly get sued by you or a subsequent owner because I helped make improvements to dogecoin.com even though it wasn't open source.