Add a REST API endpoint for getting project configuration

To start, only expose the inheritable booleans stored in the project
config, and only to users who can see refs/meta/config.

Change-Id: I299a5317fb641e84b899f8240764c4902a34c72a

gerrit-server/src/main/java/com/google/gerrit/server/project/Module.java

@@ -51,5 +51,7 @@ public class Module extends RestApiModule {
     put(DASHBOARD_KIND).to(SetDashboard.class);
     delete(DASHBOARD_KIND).to(DeleteDashboard.class);
     install(new FactoryModuleBuilder().build(CreateProject.Factory.class));
+
+    get(PROJECT_KIND, "config").to(GetConfig.class);
   }
 }