added IInstallable interface and uninstall implementation for modules. Refactoring module installation to use interface still in progress.

Oqtane.Server/Repository/Interfaces/ISqlRepository.cs

@@ -1,10 +1,12 @@
 using System.Data.SqlClient;
+using System.Reflection;
 using Oqtane.Models;
 
 namespace Oqtane.Repository
 {
     public interface ISqlRepository
     {
+        bool ExecuteEmbeddedScript(Assembly assembly, string script);
         void ExecuteScript(Tenant tenant, string script);
         int ExecuteNonQuery(Tenant tenant, string query);
         SqlDataReader ExecuteReader(Tenant tenant, string query);