Remove custom signals until we figure an actual use case

docs/examples.rst

+djWebdApp Examples
+~~~~~~~~~~~~~~~~~~
+
+Chaining blockchain calls
+-------------------------
+
+This example demonstrates how to generate an initial mint call to deploy
+whenever a new contract is deployed:
+
+.. code-block:: python
+
+    from djwebdapp_tezos.models import TezosTransaction
+    from django.db.models import signals
+    from django.dispatch import receiver
+
+
+    @receiver(signals.post_save, sender=TezosTransaction)
+    def auto_mint(sender, instance, **kwargs):
+        if not instance.address:
+            # we're not a contract or not ready
+            return
+
+        if instance.call_set.count() > 1:
+            # we have a mint already
+            return
+
+        mint = TezosTransaction.objects.create(
+            sender=instance.sender,
+            state='deploy',
+            max_fails=2,
+            contract=instance,
+            function='mint',
+            args=(
+                instance.sender.address,
+                1000,
+            ),
+        )