Support separate field names used for storage.

[alexmingoia]

This closes #119 by adding support for storing data using a field name defined by the schema.

For example, to store emailAddress as email_address, you use the name parameter:

var User = schema.define('User', {
  name: String,
  emailAddress: { type: String, name: 'email_address' }
});

I've added a test for it and updated documentation: https://github.com/alexmingoia/jugglingdb/blob/custom-fieldnames/docs/schema.md#custom-database-columnfield-names

[lwansbrough]

Thanks for this.

[yanickrochon]

How are the field names normally generated? If JugglingDB'd make usage of Underscore.String, it could make use of the _s.underscored("emailAddress") == "email_address" function.

I'd see this feature to override the default behaviour when using "weird" schemas, or normalizing models.

My 2 cents.

[qfox]

I think it's have buggy behaviour on create/update databases.

[qfox]

Just look at this: https://gist.github.com/zxqfox/19662d3ec545a149924c testing with postgres adapter. Guys. How to write tests for adapters? What should be placed in jugglingdb? Atm I didn't see any tests in jugglingdb/postgres adapter