The value of the field - this type of this value depends on the type of this field, it will most commonly be a string or an array.
Returns the value of the field, as determined by the field type.
Important: the _toString PHP magic method handles direct echoing of field values out to your templates by simply echoing the a MEOW_Field object directly, but this automatic conversion to a string does NOT happen when using the value of a field as a variable in an expression. This is where the MEOW_Field::value method must be used. See the example for the correct and incorrect way to use values in variables.