Migrate build to CMake and standard github workflows

Replace makefiles with CMakeLists.txt. This will allow for IDE and
platform agnostic builds of FFF.

Update the CI for FFF to use github workflows which don't depend on MS VC.
The workflow added will verify the pull requests sent to master buy
running 'buildandtest' which mirrors the developer workflow.

Signed-off-by: Yuval Peress <peress@google.com>

examples/embedded_ui/include/UI.h

@@ -0,0 +1,12 @@
+#ifndef UI_H_
+#define UI_H_
+
+typedef void (*button_cbk_t)(void);
+
+void UI_init();
+unsigned int UI_get_missed_irqs();
+void UI_button_irq_handler();
+void UI_register_button_cbk(button_cbk_t cbk);
+void UI_write_line(char *line);
+
+#endif /* UI_H_ */