This is for non-'Desktop' applications that have a
more limited collection of functions.

Fix switch fall-through warning

Clang with `-Wimplicit-fallthrough` enabled shows a warning here without
the break.

Extend CI tests with older c++ standards

Given that it is required for header only builds it has to be
installed too.

This informs travis that the container-based build environment can
not be used.

fix android build

Update project layout

Conflicts:
	posix.h

Based on that information less intrusive option defaults are choosen.
Additionally, packaging support is omitted.