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/Migrations/Framework/MultiDatabaseMigration.cs

@@ -0,0 +1,19 @@
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Oqtane.Interfaces;
+
+namespace Oqtane.Migrations
+{
+    public abstract class MultiDatabaseMigration : Migration
+    {
+        private readonly IEnumerable<IOqtaneDatabase> _databases;
+
+        protected MultiDatabaseMigration(IEnumerable<IOqtaneDatabase> databases)
+        {
+            _databases = databases;
+        }
+
+        protected IOqtaneDatabase ActiveDatabase => _databases.FirstOrDefault(d => d.Provider == ActiveProvider);
+    }
+}