* Modernised and cleaned up Lua bindings for input classes.
* Exposed the input_sequence_poller class to Lua and updated the
autofire and cheat plugins to use it, rather than continuing to
pretend it's part of the input manager.
* Exposed more of the natural keyboard manager, including the ability
to enable/disable individual keyboard and keypad devices like you
can from the keyboard mode menu.
* Exposed a few more things on ioport_port and input_device.
-plugins/cheat: Fixed menu item not updating visually when disabling a
cheat with UI Left.
-plugins/cheatfind: Fixed not finding the first screen after screen
enumerator was exposed as an object rather than using a table.
-bwidow.cpp, pacman.cpp: Minor cleanup to recent changes.
