Fix Tapping: release key immediately but modifier #65

- See https://github.com/tmk/tmk_keyboard/issues/60
- **Except for modifiers** a key pressed before the tapping starts should be released immediately
- 'Mod-Tap key'(like shift-;) didn't work from this fix: 4d0b3aa Fix Tapping: release of a key pressed before tap
This key sequence should register ':', not ';'. With the fix Shift is
released before settlement of tapping, this registers ';'.
    Shift   ~~___~~~~~~~
    ;(Tap)  ~~~____~~~~
Fix VERSION: add opton --always to git describe
Remove clear matrix on ADB recv error
Fix mod stuck of MODS_KEY when leaving layer #62

- Add action_util.c and remove action_oneshot.c
- Add oneshot_mods for MODS_ONESHOT
- Add weak_mods for MODS_KEY and MACRO
- weak_mods is cleared when layer switching
Add timeout option to MODS_ONESHOT #66
Fix build error and debug print PJRC stack #69 #68
Make LUFA stack as default for ADB converter
Fix ADB missing keystrokes problem Thanks, blargg! #14

- Add delay between scans to prevent overlaod of ADB keyboard controllers
- <http://geekhack.org/index.php?topic=14290.msg1068919#msg1068919>
Merge remote-tracking branch 'tmk/master' into hhkb-ex-dev