Add abstract Activity for NFC reading + writing

And change MainActivity to inherit from this.
Change title of the edit card dialog

Copy-pasted it and forgot to change it the last time around.
Update NfcSkeleton library
Folded NFC writing code into MainActivity

WriteTagActivity is now mostly useless. NFC writing is now prompted with
a dialog box.
Manage fragment tags from Utils

Some tags were being reused and could potentially interfere with other
fragment transactions.
Remove unnecessary fragment transactions in SendProgress

This fragment currently starts an activity. It's not needed right now.