Merge branch 'master' into multi-monitor

Conflicts:
	src/cocoa_window.m
	src/init.c
	tests/iconify.c
	tests/reopen.c

examples/triangle.c

@@ -10,24 +10,26 @@
 #define GLFW_INCLUDE_GLU
 #include <GL/glfw3.h>
 
+static void error_callback(int error, const char* description)
+{
+    fprintf(stderr, "Error: %s\n", description);
+}
+
 int main(void)
 {
     int width, height, x;
     GLFWwindow window;
 
+    glfwSetErrorCallback(error_callback);
+
     // Initialise GLFW
     if (!glfwInit())
-    {
-        fprintf(stderr, "Failed to initialize GLFW\n");
         exit(EXIT_FAILURE);
-    }
 
     // Open a window and create its OpenGL context
     window = glfwCreateWindow(640, 480, "Spinning Triangle", NULL, NULL);
     if (!window)
     {
-        fprintf(stderr, "Failed to open GLFW window\n");
-
         glfwTerminate();
         exit(EXIT_FAILURE);
     }