Support for writing NFC tags

[semlette]

New APIs

• NFCTag: an abstract class for NFC tags (not messages, actual tags)
• • has writable, connect and close methods
• NDEFTag: class for NDEF tags
• • has write method for writing NDEFMessages

To-do list

• [ ] Move read example in the example app to a seperate page
• [x] Create write example in the example app
• [x] Support for writing tags on Android
• [ ] Support for writing tags on iOS
• [ ] Documentation

Major release

There have been changes to the NDEFMessage- and NDEFRecord constructors. The constructors were supposed to only be used by the plugin, but somebody could be using them. So just to be sure, this will be a major release because it contains possible breaking changes.

[semlette]

Closing as work is continuing in the next branch.