rb core allows you to load custom keyboard layouts
this patch adds the ability to load a keyboard layout in a buffer
the custom layout is temporary and does not overwrite the current layout
use like so:
unsigned short kbd[64];
unsigned short *kbd_p = kbd;
if (!kbd_create_layout("ABCD1234\n", kbd, sizeof(kbd)))
kbd_p = NULL;
rb->kbd_input(buf,sizeof(buf), kbd_p);
Change-Id: I7be2bd4a1b4797a147fa70228a9749dc56ac052a
