Doc++
Updated toolchains submodule.
package: adapt Emscripten PKGBUILD to emscripten-git AUR package.
Oh Doxygen you so predictable.
doc: make section headers in class docs have sane size.

The \section Doxygen command has unnecessarily large font size when used
in class documentation, it is even bigger than the "Detailed
Description" header, which looks very ugly.

Using \subsection doesn't help, as Doxygen then complains about
\subsection without enclosing \section. Worked around that by using
Markdown `##` syntax and adding \anchor where needed. Also prefixed the
\anchor with namespace to make the identifier really unique.
Merge branch 'master' into compatibility