chore(package): update pdfjs-dist to version 1.9.560 (#1437)

Author: greenkeeper[bot]

package.json

@@ -41,7 +41,7 @@
     "karma-sauce-launcher": "1.2.0",
     "local-web-server": "2.2.4",
     "markdown": "^0.5.0",
-    "pdfjs-dist": "1.9.558",
+    "pdfjs-dist": "1.9.560",
     "rollup": "0.49.3",
     "rollup-plugin-babel": "3.0.0",
     "uglify-js": "3.1.0"