Make navigation work again.

Make navigation work again.

	* src/main/java/org/glom/web/server/libglom/Document.java:
	Add getLayoutItemFieldShouldHaveNavigation().
	* src/main/java/org/glom/web/shared/libglom/layout/LayoutItemField.java:
	Replace get/setAddNavigation() with the partly-existing
	get/setNavigationTableName(), with an empty string being no navigation,
	because this is simpler. Use the new
	Document.getLayoutItemFieldShouldHaveNavigation() method to set this.

	* src/main/java/org/glom/web/server/ConfiguredDocument.java:
	Add updateFieldsExtras() and call setNavigationTableName in it.
	getDetailsLayoutGroup(),
	* src/main/java/org/glom/web/client/activity/DetailsActivity.java
	createLayout(): Adapted.
	* src/main/java/org/glom/web/client/ui/details/DetailsCell.java
	Constructor: Adapted.

	* src/main/java/org/glom/web/shared/libglom/layout/LayoutItemPortal.java:
	Replace get/setAddNavigation() with get/setNavigation(), returning a
	TableToViewDetails class with both the table name and UsesRelationship,
	because both are need. The previous code used java-libglom's output
	variable (strangely, via sharedptr) to return both, but we cannot really
	do that in Java.
	* src/main/java/org/glom/web/server/database/RelatedListNavigation.java:
	getNavigationRecord(): Adapt. However, we cannot actually use the cache
	here because it somehow gets set to null during deepCopy(). I must test this.
	* src/test/java/org/glom/web/server/libglom/DocumentTest.java
	testGetSuitableTableToViewDetails(): Adapted.

	TODO: Find out why deepClone() is not quite working.