Enable the table selector in the DetailsView.

Enable the table selector in the DetailsView.

* 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:
Remove getDefaultDetailsLayout(). The default layout is now returned
by the getDetailsLayout() method when the table name is an empty
string.
* src/main/java/org/glom/web/client/activity/DetailsActivity.java: Add
event handler for table change event. Change to using
getDetailsLayout() for the default details layout.
* src/main/java/org/glom/web/client/place/DetailsPlace.java: Add table
name to URL token.
* src/main/java/org/glom/web/client/ui/ListViewImpl.java: Use table
when navigating to the details place.