[core] Add Gamepad Vibration functionality

[ghost]

Issue description

I wish there was some functionality to vibrate the gamepad with raylib for some enhanced haptics experience. Xbox and PS gamepads support this out of the box for desktop & consoles, HTML5's Gamepad API still doesn't have any functionality for this, but in that platform the method would just not do anything.

I propose there would be 2 methods:

Code Example

bool IsGamepadVibrationSupported(int gamepad);   // checks whether target gamepad device supports vibration
void SetGamepadVibration(int gamepad, float leftMotor, float rightMotor);  // sets the vibration strength for the gamepad motors, 0 to 1

[raysan5]

This features depends on GLFW, at least for PLATFORM_DESKTOP. Related to glfw/glfw#57

[raysan5]

About gamepad vibration for PLATFORM_WEB, some related info:

• https://developer.mozilla.org/en-US/docs/Web/API/GamepadHapticActuator
• https://www.w3.org/TR/vibration/
• Vibrate feature for Gamepad w3c/gamepad#19

[OkiStuff]

has anyone added Gamepad Vibration for web yet?

[raysan5]

@OkiStuff I'm afraid not.

[raysan5]

As this issue depends on an external library, I'm closing it. Feel free to open the issue on the specific repo that should implement it or just send a PR for review.