File definition (in module) has FilePublishingAssociatedContentType attribute. In the actual sense it means a binding between the Page Layout and the content type. If you fail to provide one, the SharePoint framework will make use of the Page content type from Publishing feature. The value for this property should be in form:
;#[Content type name];#[Content type ID];#
reSP allows you to select value from the drop-down list.
Just use Ctrl+Space shortcut.