Updated dependencies: sharp, createerror, httperrors and passerror

sharp to 0.13.0
createerror to 1.0.1
httperrors to 1.2.0
passerror to 1.1.1

package.json

@@ -8,21 +8,21 @@
     "bin": "bin"
   },
   "dependencies": {
-    "createerror": "0.5.1",
+    "createerror": "1.0.1",
     "exif-reader": "1.0.0",
     "gm": "1.19.0",
     "hijackresponse-nobackpressure": "1.0.2",
-    "httperrors": "1.1.0",
+    "httperrors": "1.2.0",
     "icc": "0.0.2",
     "inkscape": "0.0.5",
     "jpegtran": "0.2.0",
     "mime": "1.3.4",
     "optimist": "0.6.1",
     "optipng": "0.3.1",
-    "passerror": "0.0.1",
+    "passerror": "1.1.1",
     "pngcrush": "0.2.0",
     "pngquant": "0.6.0",
-    "sharp": "0.12.0",
+    "sharp": "0.13.0",
     "underscore": "1.8.3"
   },
   "optionalDependencies": {