title: Flask migrate does not detect column autoincrement changes?
body: <p>I have change my model class with id from autoincrement=False to autoincrement=True but Flask Migrate package does not dectect change to apply to the database? How can I fix this?</p>
  
  <pre><code>class User(db.Model):
      __tablename__ = 'users'
      id = db.Column(db.Integer, unique=True, primary_key=True, autoincrement=True)
  </code></pre>
  
  <p>The migrate command log:</p>
  
  <pre><code>INFO  [alembic.runtime.migration] Context impl MySQLImpl.
  INFO  [alembic.runtime.migration] Will assume non-transactional DDL.
  INFO  [alembic.env] No changes in schema detected.
  </code></pre>