[#790] added a `force` flag that allow to override the current shake effect when repeatedly calling the `shake` function
[#790] added a `force` flag that allow to override the current shake effect when repeatedly calling the `shake` function

melonjs/melonJS,rlugojr/melonJS,melonjs/melonJS,rlugojr/melonJS,rlugojr/melonJS