Add user-agent to the request headers to be less shady

functions.js

@@ -7,6 +7,12 @@ var options = require('./options.js');
 
 var cache = {}
 
+var request_options = {
+    'headers': {
+        'user-agent': options.userAgentString
+    }
+}
+
 // Note: http://site.com/image/icons/home.png -> http://site.com/image/icons
 function absoluteURLPath (aURL) {
     var URL = url.parse(aURL)
@@ -49,7 +55,7 @@ function retrieveFile (aAbsBasePath, aFilePath, aBinary) {
             return cache[cacheKey]
         } else {
             try {
-                var res = request('GET', fullFilePath)
+                var res = request('GET', fullFilePath, request_options)
 
                 if (!options.suppressVerboseOutput)
                     console.warn('Retrieving file', fullFilePath, '...')

options.js

@@ -1,6 +1,9 @@
+'use strict'
+
 var options = {
     outputFinalResultAsBase64: false,
-    suppressVerboseOutput: false
+    suppressVerboseOutput: false,
+    userAgentString: 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.76 Safari/537.36',
 }
 
 module.exports = options