Add migration to remove status column

This is safe to run once the preceding commits are deployed all the way
out to production.

Author: nickstenning

h/migrations/versions/0d4755a0d88b_remove_status_column_from_user_table.py

@@ -0,0 +1,24 @@
+"""Remove status column from user table
+
+Revision ID: 0d4755a0d88b
+Revises: 2494fea98d2d
+Create Date: 2016-03-21 20:07:07.002482
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = '0d4755a0d88b'
+down_revision = '2494fea98d2d'
+
+from alembic import op
+import sqlalchemy as sa
+
+
+def upgrade():
+    # Dropping a column is O(1) so this is safe to run against a production
+    # database.
+    op.drop_column('user', 'status')
+
+
+def downgrade():
+    op.add_column('user', sa.Column('status', sa.Integer()))