Use new clouddocs-maven-plugin glossary option

clouddocs-maven-plugin 1.13 has a simpler way to include the
glossary instead of copying files around. Use this new option.

Visually inspected, both PDF and HTML pages contain glossary with
content.

Change-Id: I8ff4d1f437492d1b6f0ff7daa90a228ed4d4375f