An option to 'loosely' follow unmanaged models in certain scenarios

[hannylicious]

There should be an option to follow unmanaged models 'strictly' (which should be the default); but in some instances - people have projects with unmanaged models that are a 'bare bones' basic model, because the columns are already setup in the DB and they just want a model to be able to interface with them.

For example maybe there is a model that on the database level allows null fields in a column. The developer builds out a basic model, just the 'bare minimum model' to get working. It just has the column name and type (it does not have null=True).

In it's current form, there will be an issue when the user tries to save something to that row if the data being entered has a null value, despite that being a perfectly allowable outcome (on the staging/production dbs for example).

Perhaps an argument like --loose would make it create the fields in the 'loosest' sense possible (allowing null/blank for any/all) for when a user needs that.