docs: optimize head section of templates Reordered the head section of website/www using capo.js to improve speed. Tried to do the same for the doc/_template/layout.html. Due to a bug in sphinx, we get duplicate viewport tags. https://github.com/sphinx-doc/sphinx/issues/11699 but I think it's harmless.

try:
    # Python 3+
    from ssl import SSLError
except (ImportError, AttributeError):
    # Python 2.5-2.7
    from socket import sslerror as SSLError    # noqa: F401