Merge latest nfcd code

1. Add formatNdef API
- This API is not yet tested and used. Only implement the formatNdef for broadcom NCI based code
2. Add NDEF_WRITABLE technology
- Add it according to GONK Spec
3. Prevent double enable/disable
- Do not do enable/disable multiple times when it is already in that state
4. Fix enable NFC crash : do not enter low power mode just after enabling
- This is a temporarily solution for this bug. It will be fix in 
  https://bugzilla.mozilla.org/show_bug.cgi?id=934835
5. Refine code
6. Update NdefDetail structure according to GONK protocol spc change