$field->persist attribute

[georgehristov]

schema/src/Migration.php

Line 230 in a430753

$this->field($field->actual ?: $field->short_name, ['type' => $type]); // todo add more options here

Suggest to introduce $persist attribute in the atk4\data\Field class with functionality as follows:

• $persist = false takes over $never_persist
• $persist = ['length' => 5] array as list of parameters which atk4\schema\Migration class will use
• $persist = ['type' => 'text'] type key will determine field individual persistence type

[georgehristov]

Similar concept already laid out in atk4/data/feature/number-field branch