Fixed text domain issues

git-svn-id: https://plugins.svn.wordpress.org/easy-digital-downloads-discount-widget/trunk@862076 b8457f37-d9ea-0310-8a92-e5e31aec5664
Remove incorrectly named file

git-svn-id: https://plugins.svn.wordpress.org/easy-digital-downloads-discount-widget/trunk@862087 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fixed missing variable error

git-svn-id: https://plugins.svn.wordpress.org/easy-digital-downloads-discount-widget/trunk@862094 b8457f37-d9ea-0310-8a92-e5e31aec5664