Added suuport to inject an IOqtaneDatabase in EntityBuilders to allow each Database to control certain Migration behaviors. Also updated Installer to dynamically build Database Configuration section

Oqtane.Server/Databases/Interfaces/IMultiDatabase.cs

@@ -0,0 +1,10 @@
+using System.Collections.Generic;
+using Oqtane.Interfaces;
+
+namespace Oqtane.Repository.Databases.Interfaces
+{
+    public interface IMultiDatabase
+    {
+        public IEnumerable<IOqtaneDatabase> Databases { get; }
+    }
+}