Cosmetic: moved Anchor class closer to the code for other similar classes in the module, and updated inline documentation for TOC, HTML_components, ExternalFile, Stylesheet and Script classes.
Cosmetic: moved Anchor class closer to the code for other similar
classes in the module, and updated inline documentation for TOC,
HTML_components, ExternalFile, Stylesheet and Script classes.

xia2/xia2,xia2/xia2