GitLab

Make sure Western digits are used where Western digits are required; tests (see https://github.com/mangstadt/ez-vcard/issues/113)

Update to Android gradle plugin 4.1.0; increase target SDK level to 30; update BatchOperation to new API definition

- don't delete all raw contact data rows, but only the ones we use to insert ourselves

- EMAIL: drop TYPE=internet and TYPE=x400 because Android only knows Internet email addresses
- EMAIL: treat TYPE=other (which is not specified in vCard RFCs) as "other" email address for better compatibility
- upgrade Apache Commons text library

* use Kotlin getters/setters, if possible
* simplify interfaces
* reduce importance of ContactsStorageException (now used as a separate exception only,
  not as a wrapper for RemoteException)

* some NPE fixes