Lua script that enables handling of certain commands depending on where
the mouse pointer is. Mostly useful for mouse-wheel handling via
input.conf.
Example:
MOUSE_BTN3 script-message-to zones commands "*-left: add volume +5"
"default: seek +10"
MOUSE_BTN4 script-message-to zones commands "*-left: add volume -5"
"default: seek -10"
Will changes behavior of Mouse Wheel Up/Down to alter volume if mouse is
in the left zone of the window, but re-adds the default to seek if wheel
is used on other parts.