fix include

Change-Id: I8067b681e257a45eee0972c53c408f7c19817afb

bin/nodejs/binding.gyp

@@ -4,7 +4,7 @@
       "target_name": "dring",
       "sources": [ "ring_wrapper.cpp" ],
       'include_dirs': ['../../src/'],
-      'libraries': ['-L../../src/.libs/', '-lring'],
+      'libraries': ['-L<(module_root_dir)/../../src/.libs/', '-lring'],
       'cflags!': [ '-fno-exceptions' ],
       'cflags_cc!': [ '-fno-exceptions' ]
     }