[Schema+config change] Comment editing (#396)

* Comment editing
* Optional time limit for comment editing

migrations/versions/cf7bf6d0e6bd_add_edited_time_to_comments.py

@@ -0,0 +1,30 @@
+"""Add edited_time to Comments
+
+Revision ID: cf7bf6d0e6bd
+Revises: 500117641608
+Create Date: 2017-10-28 15:32:12.687378
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'cf7bf6d0e6bd'
+down_revision = '500117641608'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('nyaa_comments', sa.Column('edited_time', sa.DateTime(), nullable=True))
+    op.add_column('sukebei_comments', sa.Column('edited_time', sa.DateTime(), nullable=True))
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_column('sukebei_comments', 'edited_time')
+    op.drop_column('nyaa_comments', 'edited_time')
+    # ### end Alembic commands ###