Added migration to support new password_hash format

.gitignore

@@ -2,3 +2,6 @@ config.yaml
 */*_modules/
 .coverage
 .cache
+__pycache__
+.idea/
+*.iml

server/szurubooru/migrations/versions/9ef1a1643c2a_increase_password_hash_max_field_length.py

@@ -0,0 +1,30 @@
+'''
+Alter the password_hash field to work with larger output. Particularly libsodium output for greater password security.
+
+Revision ID: 9ef1a1643c2a
+Created at: 2018-02-24 23:00:32.848575
+'''
+
+import sqlalchemy as sa
+from alembic import op
+
+
+revision = '9ef1a1643c2a'
+down_revision = '02ef5f73f4ab'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+
+    op.alter_column('user', 'password_hash',
+               existing_type=sa.VARCHAR(length=64),
+               type_=sa.Unicode(length=128),
+               existing_nullable=False)
+
+
+def downgrade():
+    op.alter_column('user', 'password_hash',
+               existing_type=sa.Unicode(length=128),
+               type_=sa.VARCHAR(length=64),
+               existing_nullable=False)