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* fix: <ul><li> list item in the <ol><li> rendering as numbered list, thank you usaturn!
* transplant many macro/header parts from sphinx basic theme.
* separate layout.html into some sub templates:
* globalnavigation.html : top-right 3 icons
* globaltoc.html : global toctree for sidebar
* localtoc.html : local toctree for sidebar
* relations.html : next/pref link for sidebar
* searchbox.html : search box for sidebar
* sourcelink.html : source link for sidebar