Build more demos with CI #743

	name: C/C++ CI

	on: [push, pull_request]

	jobs:
	build:

	runs-on: ubuntu-latest

	steps:
	- uses: actions/checkout@v1
	- name: apt-update
	run: sudo apt-get update -qq
	- name: apt get glfw
	run: sudo apt-get install -y --no-install-recommends liballegro5-dev liballegro-image5-dev liballegro-ttf5-dev libglfw3 libglfw3-dev libglew-dev libsdl2-dev libwayland-dev libx11-dev libxft-dev
	- name: build allegro5
	run: make -C demo/allegro5
	- name: build glfw_opengl2
	run: make -C demo/glfw_opengl2
	- name: build glfw_opengl3
	run: make -C demo/glfw_opengl3
	- name: build glfw_opengl4
	run: make -C demo/glfw_opengl4
	- name: build glfw_vulkan
	run: make -C demo/glfw_vulkan
	- name: build sdl_opengl2
	run: make -C demo/sdl_opengl2
	- name: build sdl_opengl3
	run: make -C demo/sdl_opengl3
	- name: build sdl_opengles2
	run: make -C demo/sdl_opengles2
	- name: build sdl_renderer
	run: make -C demo/sdl_renderer
	- name: build sdl2surface_rawfb
	run: make -C demo/sdl2surface_rawfb
	- name: build wayland_rawfb
	run: make -C demo/wayland_rawfb
	- name: build x11
	run: make -C demo/x11
	- name: build x11_opengl2
	run: make -C demo/x11_opengl2
	- name: build x11_opengl3
	run: make -C demo/x11_opengl3
	- name: build x11_rawfb
	run: make -C demo/x11_rawfb
	- name: build x11_xft
	run: make -C demo/x11_xft
	- name: build example
	run: make -C example

Provide feedback