added shuffle stack shortcut

[RomanNovo]

Fixes/Solves
Solved Issue-111
#111

For default key is Z

[drwhut]

Thank you for the PR! I've just got a few points/questions:

• The shortcut should be able to be changed in the options menu, under "Key Bindings".
• In CameraController, we may want to account for the fact the player might be hovering one, or multiple, pieces. If multiple pieces are being hovered, do we allow the player to shuffle all the stacks being hovered, or none at all?
• Should we only allow stacks to be shuffled when they are selected, rather than if the player is just hovering the mouse over them?

[RomanNovo]

1. Added
2. In original Tabletop (actually checked right now) Shuffling with multiple pieces selected shuffled them separatly.
3. Again, in original version, select stack is not required for shuffled. Hover is enough

[drwhut]

Just a few changes needed for the options menu.

[drwhut]

Think the tooltip needs to be a little bit more descriptive.

[drwhut]

Thank you! I'll test it on my end before approving (including the echo, I need to check the server is not overloaded with requests).

[drwhut]

With the echo events, the client sends requests to the server around every 30ms, which is too fast in my opinion.

We can either:

• Keep detecting echo events, but add a timeout to request_shuffle on the server side (e.g. 500ms, or 1000ms?)
• Not detect echo events.

[RomanNovo]

Screw this. Save idea for later. Will delete echo event

[drwhut]

Looks good, will test again before merging.