Merge pull request #6 from awieser/master

added inRelease for fixing bug when emulating.
added nfc var definition - fixes "nfc’ was not declared in this scope" error
Merge pull request #7 from pleone/master

added nfc var definition - fixes "nfc’ was not declared in this scope"
Merge branch 'master' of github.com:Seeed-Studio/PN532