We used to have lol::map::empty() to empty maps, but in std::map
this method is called clear(). It sounds safe to harmonise between
our types and have lol::array::clear() too.

Seems to still build in lol, will check other works to be sure

Added macros to help basic setup

getter default params are better now

Next pass is clean-up and fix of all the old usage

Will resume on other computer.

- removed 0 CR characters
 - removed 7 trailing whitespaces
 - replaced 332 tabs with spaces

- Most recent version is in with index buffer support

This will allow us to generate sounds on the fly on several dedicated
channels. Until now we could only play fully loaded samples.

Input was broken, as well as palette generation, and even texture
upload. Should be all good now.

We have no hope of extending lua_State to add more data to it, because
that object may be created by Lua itself, for instance within a coroutine,
and it has no knowledge of our version of the object.

This will help us deal with shader name collision. Breaks the Windows
build for the moment, unfortunately.

For now the flags are: --disable-doc --disable-test
--disable-samples --disable-tutorial.

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

Not all programs support this feature for now, but that’s because they
don’t support the scene framework either, and will need patching. Also
the default postprocess is deliberately exaggerated for now.

We already have the convenient degrees() and radians() functions to convert
between angle formats. This commit involves a lot of refactoring here and
there and I may have missed some places where conversions were needed. But
hopefully there aren’t may such places.

This is to avoid confusion with Scene::AddTile().