Migration script to populate the provider.

- initial build of this ONLY support MMG so we can assume that all existing entries are all MMG, so any nulls == MMG.
- This PR will put in fire text so not so safe to keep doing this back and forward.

migrations/versions/0091_add_inbound_provider.py

@@ -1,13 +1,13 @@
 """empty message
 
-Revision ID: 0090_add_inbound_provider
+Revision ID: 0091_add_inbound_provider
 Revises: 0090_inbound_sms
 Create Date: 2017-06-02 16:07:35.445423
 
 """
 
 # revision identifiers, used by Alembic.
-revision = '0090_add_inbound_provider'
+revision = '0091_add_inbound_provider'
 down_revision = '0090_inbound_sms'
 
 from alembic import op

migrations/versions/0092_populate_inbound_provider.py

@@ -0,0 +1,22 @@
+"""empty message
+
+Revision ID: 0092_populate_inbound_provider
+Revises: 0091_add_inbound_provider
+Create Date: 2017-05-22 10:23:43.939050
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '0092_populate_inbound_provider'
+down_revision = '0091_add_inbound_provider'
+
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+def upgrade():
+    op.execute("UPDATE inbound_sms SET provider='mmg' WHERE provider is null")
+
+
+def downgrade():
+    op.execute("UPDATE inbound_sms SET provider=null WHERE provider = 'mmg'")