Update the alembic generator template to be PEP friendly

migrations/script.py.mako

@@ -1,19 +1,18 @@
-"""${message}
+"""
 
 Revision ID: ${up_revision}
 Revises: ${down_revision}
 Create Date: ${create_date}
 
 """
-
-# revision identifiers, used by Alembic.
-revision = ${repr(up_revision)}
-down_revision = ${repr(down_revision)}
-
 from alembic import op
 import sqlalchemy as sa
 ${imports if imports else ""}
 
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+
+
 def upgrade():
     ${upgrades if upgrades else "pass"}