• Add the scripting option to LexborHTMLParser, which parses <noscript> the way a browser
  with scripting enabled does: its content becomes raw text, so a <noscript> in <head> no
  longer pushes the head elements after it into <body>. The default is unchanged.
• Add template_fragments() for reaching the content of <template> elements
  which are ignored by HTML5 compliant parsers.
• Do not replace <-undef> it not longer possible to get it.
• The internal <html> wrapper of an HTML fragment is no longer reported as the parent of
  the fragment's top-level nodes.
• create_tag() no longer returns None for the tags whose start tag the HTML parser drops
  (html, head, body, caption, col, colgroup, frame, frameset, tbody, td,
  tfoot, th, thead, tr).
• Fix inner_html covering only the first top-level node of an HTML fragment.
• Improve the speed of comment extraction
• Improve the speed of len(attrs) by counting the attribute list directly
• Fix encoding initialization when encoding=True.