src: update NODE_MODULE_VERSION to 60

Major V8 updates are usually API/ABI incompatible with previous
versions. This commit adapts NODE_MODULE_VERSION for V8 6.3.

Refs: https://github.com/nodejs/CTC/blob/master/meetings/2016-09-28.md

PR-URL: #16271
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Myles Borins <myles.borins@gmail.com>

Author: targos

src/node_version.h

@@ -103,9 +103,10 @@
  * V8 6.0: 57
  * V8 6.1: 58
  * V8 6.2: 59
+ * V8 6.3: 60
  *
  * More information can be found at https://nodejs.org/en/download/releases/
  */
-#define NODE_MODULE_VERSION 59
+#define NODE_MODULE_VERSION 60
 
 #endif  // SRC_NODE_VERSION_H_