Touchscreen Button Configurator (Basic): Add options for bottom buttons

[ChrisNZL]

Currently in 0.3.7a, there are no options available for the bottom buttons.

Need to add:

• [x] Height positioning
• [ ] Width
• [ ] Size / scaling
• [ ] Arrangement order
• [ ] Dead zone, or extra width, on the side buttons, to handle clashing with the movement arrows and combat buttons.

[ChrisNZL]

0.3.7k:

• Added option for bottom button vertical position. Good enough for now.