Sync uglify options with lodash-cli.

lib/common/uglify.options.js

@@ -1,16 +1,16 @@
 module.exports = {
-  'mangle': true,
   'compress': {
-    'comparisons': false,
-    'keep_fargs': true,
     'pure_getters': true,
     'unsafe': true,
     'unsafe_comps': true,
     'warnings': false
   },
+  'mangle': {
+    'except': ['define']
+  },
   'output': {
     'ascii_only': true,
-    'beautify': false,
+    'comments': /^!|@cc_on|@license|@preserve/i,
     'max_line_len': 500
   }
 };