implement some stuff to make exaple SDL app run

NOTE: the main addition in this commit is WIP support for apps which
render on an EGL surface obtained using ANativeWindow_fromSurface

currently, this EGL surface is obtained by creating a 700x700 pixel
window with GLFW (the 700x700 size is hardcoded in several places)
and only Wayland is supported

ideally, we'd want to use a wayland subsurface to position the EGL
surface above the Surface widget it's associated with (and do
whatever for X11)

src/api-impl/android/hardware/usb/UsbManager.java

@@ -0,0 +1,9 @@
+package android.hardware.usb;
+
+import java.util.HashMap;
+
+public class UsbManager {
+	public HashMap getDeviceList() {
+		return new HashMap();
+	}
+}