wayland: Follow _glfwInputChar() type change
Fixed name of xkbcommon pkg-config module.
Fixed Wayland EGL pkg-config module name.

The wayland-egl module also includes wayland-client.

Fixes #317.
Fixed crash on Wayland with DRM-backend.

Fixes #319.
Fixes #301.
Added credit.
Using a light grey syntax highlighting theme.
Merge pull request #322 from glfw/light-grey-highlight

Using a light grey syntax highlighting theme.
Restored smaller Doxygen code block padding.

This is a revert of db5b089cee.
Fixed typo.
Added custom Doxygen layout file.
Made events test monitor callback static.
Merge remote-tracking branch 'upstream/master'