Allow use of translations via, for instance, &lang=de in the URL.

Allow use of translations via, for instance, &lang=de in the URL.

	* pom.xml: Use the unstable java-libglom 1.21 version.

	* src/main/java/org/glom/web/client/OnlineGlomService.java:
	* src/main/java/org/glom/web/client/OnlineGlomServiceAsync.java
	* src/main/java/org/glom/web/server/OnlineGlomServiceImpl.java:
	init(): Instead of calling TranslatableItem.set_current_locale()
	(now removed), call ConfiguredDocument.setDefaultLocaleID().
	However, this is only for default locales, which are not needed to
	change the locale in the URL.
	getDocumentInfo(), getListViewLayout(), getSortedListViewData(),
	getDetailsData(), getDetailsLayoutAndData(), getRelatedListData(),
	getSortedRelatedListData(): Add a localeID parameter, so we can get the
	layout for a particular locale.
	* src/main/java/org/glom/web/server/ConfiguredDocument.java:
	Add get/setDefaultLocaleID().
	getDocumentInfo(), getListViewData(), getRelatedListData(),
	getDetailsLayoutGroup(), getListViewLayoutGroup(),
	createLayoutItemPortalDTO(), convertToGWTGlomLayoutItemField(): Add a
	localeID parameter, so we can get the layout for a particular locale.

	* src/main/java/org/glom/web/client/place/HasSelectableTablePlace.java:
	* src/main/java/org/glom/web/client/place/DetailsPlace.java:
	* src/main/java/org/glom/web/client/place/ListPlace.java:
	Parse and construct a lang parameter too.

	* src/main/java/org/glom/web/client/activity/DocumentSelectionActivity.java:
	start(): Pass the defaultLocaleID to addDocumentLink(). It is then
	passed to subsequent methods and constructors.
	* src/main/java/org/glom/web/client/activity/DetailsActivity.java:
	* src/main/java/org/glom/web/client/activity/ListActivity.java:
	Store the localeID from the *Place and pass it to other constructors
	and methods, such as OnlineGlomServiceAsync.getDetailsLayoutAndData().

	* src/main/java/org/glom/web/client/ui/DocumentSelectionView.java:
	* src/main/java/org/glom/web/client/ui/DocumentSelectionViewImpl.java:
	* src/main/java/org/glom/web/client/ui/TableSelectionView.java
	* src/main/java/org/glom/web/client/ui/TableSelectionViewImpl.java
	* src/main/java/org/glom/web/client/ui/ListView.java:
	* src/main/java/org/glom/web/client/ui/ListViewImpl.java:
	Take localeID parameters and pass them to subsequent constructors and
	methods, so that the layout is always retrieved for that locale.

	This is rather repetitive.

	Note that "" means the original (default) locale of the Glom document,
	which is usually English.