Rename wayland_buffer.{c,h} to buffer.{c,h}
Rename wayland_compositor{c,h} to compositor.{c,h}
Rename wayland_pointer.{c,h} to pointer.{c,h}
Rename wayland_shell.{c,h} to shell.{c,h}
Rename wayland_shell_surface.{c,h} to shell_surface.{c,h}