Most input and GUI files are now in a common ui/ directory. The platform/
directory is no longer, as everythyng was moved to application/ or ui/.

We now just look for SDL2/SDL.h (the regular location) and SDL.h (when
the user provides their own location for this header).

Sometimes libEGL.so can be available (provided as a symlink
by Debian diversion packages) while EGL/egl.h isn’t.

The only reason we had to keep this was for emscripten builds. We can
now use SDL v2 using “emconfigure ./configure CFLAGS="-s USE_SDL=2” and
a few additional flags.

SDL_Mixer v2 is not available in emscripten packages but either it will
be added at some time, or I will get rid of it altogether. An alternate
solution could be this code snippet I found:

    cd SDL2_mixer
    emconfigure ./configure --prefix=$(pwd)/dist --enable-music-ogg --disable-music-ogg-shared CFLAGS="-s USE_VORBIS=1"
    emmake make install

All these changes will allow us to more easily add Lol Engine as a
submodule of another Git project.

Using “Array” instead of “array” is now fully deprecated, and I replaced
the Log::Debug() etc. functions with msg::debug() etc. because log:: was
unavailable due to being a maths function.

Added up-to-date copyright notice and BOM to modified files, just in case.

disabled until the engine code itself is ported to SDL2.

any events if there is no X window.

but we can now create shared objects for each project; only the testsuite
is not building properly because of issues with STLport, and EglApp is
deactivated because AndroidApp should have precedence.

X11 to create the EGL-capable display.

of code.