Change m0110 pin configuration: swap D0 and D1
Remove procedures not neeed from init of M0110
Change keymap and enable bootmagic of M0110
Fix README of M0110
Fix to bootmagic key configurable
Merge branch 'm0110_next'
Fix USB initilaize on LUFA

- Add print messages of USB intialize procesure.
- call out sei() in earlier stage. LUFA API doc of USB_Init() says:
interrupts must be enabled within 500ms ... to ensure that the host does
not time out whilst enumerating the device
- remove matrix_init() from suspend_wakeup_init(). It is not needed in
  fact and if matrix_init() takes long time to initialize it prevents
host emnumerating the device.