Apidoc add default-exported enums

[MoonE]

This PR supersedes and closes #10512

This adds the apidoc pages for enums that are the default export of their module without any other documented members.

The following pages are now created:

module-ol_CollectionEventType.html
module-ol_ImageState.html
module-ol_MapBrowserEventType.html
module-ol_MapEventType.html
module-ol_MapProperty.html
module-ol_ObjectEventType.html
module-ol_ViewHint.html
module-ol_ViewProperty.html
module-ol_events_EventType.html
module-ol_events_KeyCode.html
module-ol_extent_Corner.html
module-ol_extent_Relationship.html
module-ol_format_FormatType.html
module-ol_interaction_Property.html
module-ol_layer_Property.html
module-ol_layer_TileProperty.html
module-ol_pointer_EventType.html
module-ol_render_EventType.html
module-ol_render_canvas_BuilderType.html
module-ol_source_TileEventType.html
module-ol_source_VectorEventType.html
module-ol_style_IconAnchorUnits.html
module-ol_style_IconOrigin.html
module-ol_webgl_ContextEventType.html

[ahocevar]

Thanks a lot for this @MoonE!