docs: add links to the CHANGELOG from the README.md for Java and Node (#701)

Author: feywind

synthtool/gcp/templates/node_library/README.md

@@ -24,6 +24,9 @@
 {{ metadata['description'] }}
 {% endif %}
 
+A comprehensive list of changes in each version may be found in
+[the CHANGELOG](https://github.com/{{ metadata['repo']['repo'] }}/blob/master/CHANGELOG.md).
+
 {% if metadata['repo']['client_documentation'] %}* [{{ metadata['repo']['name_pretty'] }} {{ metadata['repo']['language']|language_pretty }} Client API Reference][client-docs]{% endif %}
 {% if metadata['repo']['product_documentation'] %}* [{{ metadata['repo']['name_pretty'] }} Documentation][product-docs]{% endif %}
 * [github.com/{{ metadata['repo']['repo'] }}](https://github.com/{{ metadata['repo']['repo'] }})