* new models_magicavoxel_loading example

* Portable header-only file "magicavoxel_loader.h" for MagicaVoxel loader example.

* models_magicavoxel_loading example added to CMakeLists.txt and Makefile

* fix models_magicavoxel_loading example for linux.

* * vox_loader into "src/external/vox_loader.h"
 * vox file support for "models.c"
 * updated example "models/models_magicavoxel_loading.c"

* * Fix Vox_FreeArrays (removed memory leak)

* * removed magicavoxel_loader.h

* * Revert vs2019 solution

* Documenting the compiler flags

* Moved some android compiler flags and added documentation on them too.

* Some more restructuring.

Removed unnecessary comments that were self described by the code.
Added some more explanations around certain parts of CMake and especially around compiler flags.

* Delete emscripten.cmake

This file is not needed at this point. EMSDK provides a toolchain file that has a lot more things in it and is better supported. Project currently works fine with the documentation provided in Emscripten SDK on how to build projects.

* First pass file separation.

The main two files are cleaner now. Only important things can be seen. Major changes include:
- raylib_static is now the alias instead of raylib
- Repeating segments are removed and pulled into separate files into <root>/cmake
- File is reordered to make more sense
- Installs are better structured
- Library is build into an output directory "raylib" instead of "src"
- All public header files are now set as a public header file
- Source files need to be listed (it is a bad practice to capture them using wildcards and file globs)
- CMakeLists are better commented

* Second pass on the example dirs.

They are quite complex so I'm more hesitant to do major changes. Also it works pretty well. Noticed that I forgot one of the seperated files and added it into src/CMakeLists.txt.

* Returned the header copy as it was convenient to have the public headers copied.

* A better description to the variable RAYLIB_IS_MAIN

Co-authored-by: Rob Loach <robloach@gmail.com>

* Remove debug message

Co-authored-by: Rob Loach <robloach@gmail.com>

* Improvements based on review.

* Simplify the install condition to not be platform specific as it was before.

Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

* Remove some CMAKE variables as they don't affect the build in any way

Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

Co-authored-by: Rob Loach <robloach@gmail.com>
Co-authored-by: Alexander Neumann <30894796+Neumann-A@users.noreply.github.com>

* Fixed the build for web using CMake.

I found that the build for me was failing and I added some if defined checks in the core.c file where the glfwSetWindowAttrib was used. (error: implicit declaration of function 'glfwSetWindowAttrib' is invalid in C99 [-Werror,-Wimplicit-function-declaration])

I also changed some values in the toolchain file so that it correctly uses the .bat files when on windows.

* Cleaned up the additional variables (they are not important)

* Added more improvements to cmakelists

Added the option to use the system provided Emscripten toolchain to be more uniform with other libraries.

Fixed and issue which prevented example being built from cmake and also building with html extensions properly.

* Fixed ENUM to STRING because of a missed warning

We didn't use the latest version, but a compatible version, which is established by raylib-config-version.cmake.

It's ok to have a minimal version, so revert b7c0d5b6dd.

* Always use latest raylib version

* Always use latest raylib version

* Always use latest raylib version

At least on Linux, CMake seems to add automatically
the '-rdynamic' flag. As a result, Emscripten
generates a fat HTML file that does not work.
Removing it allows HTML+JS+WASM generation.

Otherwise compiling rlgl is too spammy. While at it remove
the now unneeded CheckIncludeFiles.

The example requires pthreads and now C11 <stdatomic.h>, thus skip it
if either isn't available.

This also fixes the current Travis CI build failure for the
Windows configuration.

No examples built for the Web platform functioned properly due to lack
of resources in the virtual file system provided by emscripten.

This patch addresses this problem by adding
'--preload-file local_path/resources@resources' emcc option to link
flags whenever necessary.

The default memory limit for emscripten applications is 16 mergabytes,
which might be to little for some examples, especially given that the
resources are also included in that limit.

Normally, using this option disables some asm.js optimizations, but
there's no such cost for WebAssembly.

With the recent CMake cleanup, getting raylib's dependencies for use
when building rlgl_standalone is quite straight forward, so lets enable
it again.

Fixes #508, just properly this time. :)

Remove that link_libraries_to_executable() hack and defines a proper
raylib target that can be used with target_link_libraries.

The same target is also available for external (user) code by using
find_package(raylib).

This results in:

- Remove hardcoded build directories from examples and games CMakeLists.txt
- Allow rlgl_standalone and other special examples to be built easily
- Allow CMake projects to find_package(raylib instead of fiddling with pkg-config
- Makes code a little more maintainable
- Fixes #471, #606.
- Makes code less confusing by removing the double use of PLATFORM (#584).

Note that this is still not _The Right Way_(TM), because normally
raylib-config.cmake (or its includes) would be automatically generated.
I didn't manage to get that to work though, so I went the easier route
of just wrapping pkg_check_modules for consumption by find_package.

Closes #588.

Mimic the Makefile by outputting html + js instead of LLVM IR.

src/core.c does explicitly skip including <camera.h> on Android
and tests fail. Therefore skip these failing tests.

Closes #507.

They were disabled because they failed to build,
but this patch set fixes the build on Linux and macOS.

This doesn't apply to the AppVeyor build on Windows yet;
it currently fails at linking with OpenAL.

Some people might find this handly