Update documentation.

- Convert http to https, provide archive link when possible.
- Made CPU-JIT.png more readable on dark themes;
Added a white background so there isn't black text on a black
background.

src/xenia/hid/input.h

@@ -70,7 +70,7 @@ struct X_INPUT_CAPABILITIES {
 static_assert_size(X_INPUT_CAPABILITIES,
                    sizeof(X_INPUT_GAMEPAD) + sizeof(X_INPUT_VIBRATION) + 4);
 
-// http://msdn.microsoft.com/en-us/library/windows/desktop/microsoft.directx_sdk.reference.xinput_keystroke(v=vs.85).aspx
+// https://msdn.microsoft.com/en-us/library/windows/desktop/microsoft.directx_sdk.reference.xinput_keystroke(v=vs.85).aspx
 struct X_INPUT_KEYSTROKE {
   be<uint16_t> virtual_key;
   be<uint16_t> unicode;

src/xenia/hid/xinput/xinput_input_driver.cc

@@ -99,7 +99,7 @@ X_RESULT XInputInputDriver::GetKeystroke(uint32_t user_index, uint32_t flags,
 
   // XInputGetKeystroke on Windows has a bug where it will return
   // ERROR_SUCCESS (0) even if the device is not connected:
-  // http://stackoverflow.com/questions/23669238/xinputgetkeystroke-returning-error-success-while-controller-is-unplugged
+  // https://stackoverflow.com/questions/23669238/xinputgetkeystroke-returning-error-success-while-controller-is-unplugged
   //
   // So we first check if the device is connected via XInputGetCapabilities, so
   // we are not passing back an uninitialized X_INPUT_KEYSTROKE structure: