switch to html2text() instead of strip_tags() when preparing FTS index

vendor/soundasleep/html2text/tests/html/anchors.html

@@ -0,0 +1,12 @@
+A document without any HTML open/closing tags.
+
+<hr>
+
+We try and use the representation given by common browsers of the 
+HTML document, so that it looks similar when converted to plain text.
+
+<a href="http://foo.com">visit foo.com</a> - or <a href="http://www.foo.com">http://www.foo.com</a>
+
+<a href="http://foo.com" title="a link with a title">link</a>
+
+<h2><a name="anchor">An anchor which will not appear</a></h2>