Allow all versions greater than min required version

bower.json

@@ -16,8 +16,8 @@
     "Backbone", "undo"
   ],
   "dependencies" :{
-    "underscore": "1.4.4 - 1.8.3",
-    "backbone": "1.0.0 - 1.2.1"
+    "underscore": ">=1.4.4",
+    "backbone": ">=1.0.0"
   },
   "ignore": [
     "Tests",

package.json

@@ -21,7 +21,7 @@
     "url": "https://github.com/osartun/Backbone.Undo.js/issues"
   },
   "dependencies": {
-    "backbone": "1.0.0 - 1.2.1",
-    "underscore": "1.4.4 - 1.8.3"
+    "underscore": ">=1.4.4",
+    "backbone": ">=1.0.0"
   }
 }