Why this change?
This commit updates `ThemeSettingsObjectValidator` to validate a
property's value against the validations listed in the schema.
For string types, `min_length`, `max_length` and `url` are supported.
For integer and float types, `min` and `max` are supported.
Why this change?
This change adds property value validation to `ThemeSettingsObjectValidator`
for the following types: "string", "integer", "float", "boolean", "enum". Note
that this class is not being used anywhere yet and is still in
development.
Why this change?
This is a first pass at adding an objects validator which main's job is
to validate an object against a defined schema which we will support. In
this pass, we are simply validating that properties that has been marked
as required are present in the object.
