emu/input.cpp: Fixed regression in display of some joystick inputs.
osd/interface: Split up interface classes into a few more files to
reduce where the input device interface class needs to be included.
Made OSD independent of concrete input_device class.
osd/modules/input, emu/inputdev.cpp, emu/ioport.cpp: Allow input devices
to provide tokens for controls without standard item types and
additional default input assignments. Fixes issues assigning Yen and
Backslash on Japanese keyboards.
ui/textbox.cpp: Added a fixed-content text box menu class for future
use.
Got main.h out of emu.h as it’s only used in a very small number of
places, mostly for getting the application name. Added eminline.h to
attotime.h as it's used without emu.h. Cleaned up forward declarations
in emufwd.h a little.
