This is quite a big change, Model struct has been redesigned to support multiple meshes and multiple materials, most 3d fileformats contain multiple meshes and reference multiple materials.

Consequently, multiple functions have been reviewed.

LoadOBJ(), LoadIQM(), LoadGLFT() now return a Model.

Current LoadOBJ() is not valid anymore, actually, tinyobj_loader_c library is considered for replacement.

Added some comments to loader function...

glfw/glfw@5595fa3ae6 implements a proper fix for the macOS Mojave
problem of OpenGL windows not being rendered until moved or manually
updated.

Pull in the current master and rebase the three patches we have on top:
- two commits we have for reuse of the GLFW CMake build system for Wayland
It hasn't yet to be acknowledged upstream.
- one commit removing #include <windows.h> in glfw3native.h to avoid
duplicate declarations.

Fixes #655 and #665.

- Updated dr_mp3 and implemented it
- Reviewed sampleCount vs frameCount
- Reviewed XM playing (some weird things...)

...and MacOSX OBJC types definition...

Expose native Cocoa Window again...

This implementation is a bit limited, does not support wide characters directories but it's a temporal solution...

This solution uses "io.h" (like MinGW provided one) while other modern solutions use the "windows.h", that result in duplicate symbols issues... need to review it carefully.

REVIEW: Reorganized global variables for consistency
ADDED: GetWindowHandle() to get native window handle
ADDED: GetDirectoryFiles() to get files list for a DIR

Some minor tweaks around

This should improve the Raspberry Pi experience.

Corrected issue with sound playing (pop sound at the end)

The GLFW tree distributed with raylib has two modifications:

- GLFW_PKG_{DEPS,LIBS} are exported to PARENT_SCOPE, so we can use them
  in our pkg-config file
- An intermediary glfw_objlib target is added, so we can reexport GLFW
  symbols from libraylib.a

rglfw can fix the second point, but for Wayland usage, we would have to
replicate protocol generation, so we just leverage GLFW's existing
support instead.

To make maintenance easier, I have submitted a pull request for
including these modifications to upstream GLFW.
And to make that one easier, this patch dog-foods the modifications,
so raylib users can help find regressions. :-)

glfw/glfw#1307

Corrects issue with audio on RPI

Fixes: #568

if (${PLATFORM} MATCHES "Desktop")
  target_link_libraries(${RAYLIB}_shared glfw ${GLFW_LIBRARIES})

was never true because PLATFORM STREQUAL "PLATFORM_DESKTOP"...

This fixes #551 and makes the changes suggested in #552 (commited as 965cc8ab)
unnecessary.

Replaced by fabs() that seem to work ok

This reverts commit 2d6fb5c628068757387525e190c3afdbe33ae9c6,
and adds a fix for Alien::raylib's test failures.

The tests failed because the resulting static library didn't reexport
GLFW symbols. As a fix, we now have GLFW create a CMake "object library"
target that we can link with both the static and shared raylib.

This is arguably ugly... Proper fix would probably be a GLFW upstream
object library target.

Closes #536.

We need the CMake stuff for wayland configuration.
Otherwise, we would have to replicate that ourselves.
This is the full 7ef34eb06d tree except
for tests/ examples/ and docs/

- Preparing MP3 files support
- Jumped version to raylib 2.0-dev (too many breaking changes...)

Seems tcc doesn't provide __sync_*. See #435.