added/fixed headers o-s

https://github.com/borisyankov/DefinitelyTyped/issues/1570

pdf/pdf.d.ts

@@ -1,3 +1,8 @@
+// Type definitions for PDF.js
+// Project: https://github.com/mozilla/pdf.js
+// Definitions by: Josh Baldwin <https://github.com/jbaldwin/>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
 /*
 Copyright (c) 2013 Josh Baldwin https://github.com/jbaldwin/pdf.d.ts