it supports four keyboards and two cascaded hubs

- Logical Min/Max contains signed value and needs 16 bit to indicate 255
https://github.com/jackhumbert/qmk_firmware/issues/312

Add converter for XT keyboards, fixes #309

- Add mac os garbage to git ignore.

Update config.h

Please see the post at https://deskthority.net/keyboards-f2/tmk-firmware-for-xt-keyboards-t13847.html

8da1898 Merge remote-tracking branch 'flabbergast/chibios'
f0fdd8a ChibiOS: update instructions.md.
24dd0b5 ChibiOS: update mk to match chibios/master.
cdee266 Merge branch 'develop' into chibios
221663c Fix signatre of layer state change hooks
5a364cb Merge branch 'hotfix-chibios' into develop
af664cd Merge branch 'newapi' into develop
04feeaa Clean hook codes
0ca106d Fix code and table in hook.txt
714d418 Add hook document from njbair's work
b715129 Chibios: add default location for chibios-contrib.
fb3a323 Merge branch 'master' into newapi
8b7fbbd Merge branch 'master' into develop
e49851a Chibios: add default location for chibios-contrib.

git-subtree-dir: tmk_core
git-subtree-split: 8da189851b

Match the changes in mainline chibios:
 - update chconf.h
 - update supplied ld scripts structure
 - update Teensy instructions (switch to official
    chibios and introduce contrib)

Add hardware serial support for sun_usb converter

It seems that the Sun Type 5c keyboard will not send the arrow key
codes if both shift keys are pressed.  To get bell and keyclick
working, I used Home/End as toggle keys instead.

Tested with a Sun Type 5c keyboard and a 7404 inverter.

Update macro names in bluefruit protocol

update macro names in bluefruit

Conflicts:
	tmk_core/doc/keymap.md

d5c5ac6 Merge branch 'develop'
5957682 Merge branch 'hotfix-mediakey'
a478c62 Merge branch 'hotfix-vusb'
cccebfe Merge branch 'njbair-docfix'
0aaab57 Clean up wording in keymap example
dc8bbc3 Clarify layer precedence
9e0b4c1 clarify layer documentation
915eb48 core: Fix media/consumer keys
88f90f3 Fix for VUSB configuration
3e290cd Fix including board.mk in chibios.mk
32c69e0 Merge branch 'newapi' into develop
c9a56f9 Merge remote-tracking branch 'flabbergast/chibios' into develop
01e33ea Fix chibios and mbed common.mk for hook.c
bea79d9 hook: Change func name of usb events
3e97536 hook: Change file and func names(*_hook -> hook_*)
c286d8c Merge pull request #10 from fredizzimo/chibios-contrib2
062d74e Update ChibiOS instructions
d47150f Add support for new version of ChibiOS and Contrib
62b5401 Chibios: disable LTO (link-time optimisation).
c64e9aa hooks: Fix for LUFA
54e68b0 hooks: Remove led_restore_hook
325c09d Chibios: make the default bootloader_jump redefinable (weak).
078c722 Chibios: fix STM32_BOOTLOADER_ADDRESS name.
e73cfe5 hooks: Fix for keyboard LED update
e6120c5 Implement basic hooks.
7c370e9 Chibios: Update the main chibios README.
7f0198d Chibios: implement sleep LED for STM32.
afef9b4 Fix hard-coded path of CHIBIOS
95c5b19 Merge pull request #7 from fredizzimo/sysvsize
27128a8 Sysv format for ChibiOS arm-none-eabi-size
d4b8e68 core: Fix chibios user compile options
b85d462 Merge branch 'chibios' of https://github.com/flabbergast/tmk_keyboard into flabbergast_chibios
de41aa1 core: Fix ps2_mouse.c debug print
d79d925 Removed duplicate debug message code and surrounded it with IFDEF as needed
8f28589 Chibios: Revert common.mk change (fix AVR linking problem).
ec9eff2 Chibios: cleanup usb_main code.
28c4665 Chibios: Fix a HardFault bug (wait after start).

git-subtree-dir: tmk_core
git-subtree-split: d5c5ac63e6

Extenal -> External

Clarify and clean up wording in keymap.md, section 0