Import licenses from SPDX

Fixes #326

migrations/versions/725ff70ea316_.py

@@ -0,0 +1,28 @@
+"""empty message
+
+Revision ID: 725ff70ea316
+Revises: 51be0401bb85
+Create Date: 2021-07-31 19:10:36.683434
+
+"""
+from alembic import op
+import sqlalchemy as sa
+from sqlalchemy.dialects import postgresql
+
+# revision identifiers, used by Alembic.
+revision = '725ff70ea316'
+down_revision = '51be0401bb85'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('license', sa.Column('url', sa.String(length=128), nullable=True, default=None))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('license', 'url')
+    # ### end Alembic commands ###