added serial mouse driver for Microsoft and Mousesystems mice

 * Both drivers use the interface defined in serial_mouse.h
 * They should work with any UART implementation (hardware/software UART)
 * The Microsoft driver is currently untested.
   The Mousesystems driver is confirmed to work.

Just ignore ADB Service Request

- to support Adjustable keyboard(composite device?)

Fix 'debug-off' target of hhkb to remove 'print'

Fix NKRO code when NKRO is disable

Fix READEM of hhkb and doc/build.md

Fix document on HHKB internal

Add HHKB JP support

- scan matrix about twice faster

Merge pull request #124 from kairyu/6kro

USB 6KRO with pseudo- or half- NKRO feature

Merge pull request #112 from shayneholmes/ee_nkro_use_reserved_bit

Adding NKRO virtual dip-switch, using existing bit in keymap byte.

Merge pull request #125 from tibounise/patch-1

Fixing typo

Merge pull request #126 from xauser/master

Added support for bpiphany's Kitten Paw controller

Added support for bpiphany's Kitten Paw controller (Costar Majestouch)

Change keymaps of M0110

Fixing typo

Fix debug print of ps2_mouse

Fix keymap of ps2_usb

Add Ctrl + Up(SpaceFN) -> PgUp

Make keymap_hhkb as default and change keymap_hasu

Add ISO keymap(issue #35) and use new keymap API

New branch for 6KRO feature