Add request_to_go_live_notes column to Organisation table

This column will be used to stores extra notes that should go in the
Zendesk ticket when a service belonging to that organisation requests to
go live.

migrations/versions/0290_org_go_live_notes.py

@@ -0,0 +1,21 @@
+"""
+
+Revision ID: 0290_org_go_live_notes
+Revises: 0289_precompiled_for_all
+Create Date: 2019-05-13 14:55:10.291781
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+revision = '0290_org_go_live_notes'
+down_revision = '0289_precompiled_for_all'
+
+
+def upgrade():
+    op.add_column('organisation', sa.Column('request_to_go_live_notes', sa.Text(), nullable=True))
+
+
+def downgrade():
+    op.drop_column('organisation', 'request_to_go_live_notes')