Implemented full evdev keyboard text support

This is based on the Linux kernel driver, and has fallback mapping tables in case we aren't connected to a virtual terminal.

configure

@@ -23348,7 +23348,7 @@ $as_echo "#define SDL_TIMER_UNIX 1" >>confdefs.h
         fi
         # Set up files for evdev input
         if test x$use_input_events = xyes; then
-            SOURCES="$SOURCES $srcdir/src/core/linux/SDL_evdev.c"
+            SOURCES="$SOURCES $srcdir/src/core/linux/SDL_evdev*.c"
         fi
         ;;
     *-*-cygwin* | *-*-mingw32*)