Don't grab mouse button when clicking on close button in input_confirm
Add buttons for mapping joystick buttons to config menu
Allow using CTRL+Delete to clear keybinds when prompted
Fix not being able to reach the bottom of WidgetScrollBox with the knob
Turn off ENABLE_JOYSTICK if no joysticks are present
Merge pull request #1107 from dorkster/input

Joystick & interface improvements