Add ProjectDashboardsScreen

This screen displays a table with a list of dasboards for the
current project.  Each dashboard entry is a link to the actual
dashboard.  The dashboards are grouped together in sections
named after their refs.

Change-Id: I3c88dc7771d381906f2f5e8575f18aa86859b465

gerrit-gwtui/src/main/java/com/google/gerrit/client/admin/AdminConstants.java

@@ -106,6 +106,7 @@ public interface AdminConstants extends Constants {
   String projectAdminTabBranches();
   String projectAdminTabAccess();
   String projectListQueryLink();
+  String projectAdminTabDashboards();
 
   String plugins();
   String pluginEnabled();