Merge branch 'master' of github.com:rm-hull/max7219

* 'master' of github.com:rm-hull/max7219:
  Update README.md
Update README.md
openSPI returns the device configured
Merge branch 'master' of github.com:rm-hull/max7219

* 'master' of github.com:rm-hull/max7219:
  Update README.md
Merge branch 'master' into cascaded

* master:
  openSPI returns the device configured
  Update README.md