#89: Implement revocation command

• create revocation command and related revocation.py file
• write tests for revocation.py
• initiate identity module
• write tests for identity module

Close #89 (closed), #413 (closed), #416 (closed).

silkaj/blockchain_tools.py

@@ -48,3 +48,7 @@ class HeadBlock:
     def get_head(self):
         client = ClientInstance().client
         return client(blockchain.current)
+
+
+def get_currency():
+    return (HeadBlock().head_block)["currency"]