Add DUBP Mnemonic example

Add a DUBP Mnemonic example in examples folder.

Add the official Python Mnemonic package as dependency.

Requires MR #160 (closed) to be merged.

changed milestone to %1.0.0

added Authentication Crypto labels

added Examples label

marked this issue as related to #150 (closed)

mentioned in merge request !130 (merged)

marked this issue as related to #168 (closed)

mentioned in issue #168 (closed)

mentioned in commit 075738c8

mentioned in merge request !142 (merged)

mentioned in commit 51707499

closed with merge request !142 (merged)