wxWidgets 3.1.5+ on Linux will compile with the Wayland EGL
canvas as the backend instead of the X11 backend. This requires a
version of GLEW compiled with the proper EGL defines and a different
header/code for certain parts that are X11 GLEW specific.
This introduces an in-tree version of GLEW that will be built with the
GLEW_EGL flag then statically linked into the KiCad executables when
EGL support is needed.
The use of printf, wxLogDebug, and std::err/std::out causes excessive
debugging output which makes finding specific debugging messages more
difficult than it needs to be.
There is still some debugging output in test code that really needs to
be moved into a unit test.
Add debugging output section to the coding policy regarding debugging
output.
This prevents deadlocks when exceptions are thrown and the context
ends up not getting unlocked.
It also removes an earlier hack to try and minimize this which
didn't work anyway.