title: EF 7 Code first DB creation issue
body: <p>I followed a tutorial on pluralsight for ASP .NET 5 and EF 7 using Code First DB.
  This is the connection string : </p>
  
  <pre><code>"WorldContextConnection": "Server=CVU-OCTAVIANE\\SQLEXPRESS;Database=TheWorldDB;Trusted_Connection=true;"
  </code></pre>
  
  <p>I added the initial migration (which worked fine) and then I tried to use a EF 7 feature to create the DB automatically: I created a Context type class where I used Database.EnsureCreated() to create the DB on the first run. This is the context class:</p>
  
  <pre><code>public class WorldContext : DbContext
  {
      public WorldContext()
      {
          Database.EnsureCreated();
      }
  
      public DbSet&lt;Trip&gt; Trips { get; set; }
      public DbSet&lt;Stop&gt; Stops { get; set; }
  
      protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
      {
          var connString = Startup.Configuration["Data:WorldContextConnection"];
  
          optionsBuilder.UseSqlServer(connString);
          base.OnConfiguring(optionsBuilder);
      }
  }
  </code></pre>
  
  <p>When I ran the project "A severe error occurred on the current command"</p>
  
  <p>Thanks</p>