Fixed cursor outside new full screen windows.

The cursor was not positioned over newly created full screen windows,
leading to confusing behavior like invisible cursor or window
iconification.

This fix is a stop-gap until the direct cursor position work is merged.

Fixes #111.

src/window.c

@@ -246,8 +246,21 @@ GLFWAPI GLFWwindow* glfwCreateWindow(int width, int height,
     // Restore the previously current context (or NULL)
     _glfwPlatformMakeContextCurrent(previous);
 
-    if (wndconfig.monitor == NULL && wndconfig.visible)
-        _glfwPlatformShowWindow(window);
+    if (wndconfig.monitor)
+    {
+        int width, height;
+        _glfwPlatformGetWindowSize(window, &width, &height);
+
+        window->cursorPosX = width / 2;
+        window->cursorPosY = height / 2;
+
+        _glfwPlatformSetCursorPos(window, window->cursorPosX, window->cursorPosY);
+    }
+    else
+    {
+        if (wndconfig.visible)
+            _glfwPlatformShowWindow(window);
+    }
 
     return (GLFWwindow*) window;
 }