Support hooks with custom node version.

testing/resources/node_0_11_8_hooks_repo/bin/main.js

@@ -0,0 +1,4 @@
+#!/usr/bin/env node
+
+console.log(process.version);
+console.log('Hello World');

testing/resources/node_0_11_8_hooks_repo/hooks.yaml

@@ -0,0 +1,5 @@
+-   id: node-11-8-hook
+    name: Node 0.11.8 hook
+    entry: node-11-8-hook
+    language: node
+    language_version: 0.11.8

testing/resources/node_0_11_8_hooks_repo/package.json

@@ -0,0 +1,5 @@
+{
+    "name": "node-11-8-hook",
+    "version": "0.0.1",
+    "bin": {"node-11-8-hook": "./bin/main.js"}
+}