Is there a mechanism for generating a book index if there is the follwing markup in the html document?
<span class="role-index-term" id="__IDX1__"><span class="role-index-term-1">Sample Mainentry</span><span class="role-index-term-2">Sample Subentry</span></span>
<span class="role-index-term" id="__IDX1__"><span class="role-index-term-1">Sample Mainentry</span><span class="role-index-term-2">Sample Subentry</span></span>