Enable the "Extend from a template" section and fix the link in this document to this section.

[arkoppan]

The section "Extend from a template" was not showing up in the document at all due to moniker range incorrectly placed. And also because of this, the link ("extending from a template" under "Variable reuse" section) further down in the document to this section was not working. Updated the moniker-range for the section "Extend from a template".