title: PetaPoco - setting transaction isolation level
body: <p>Using PetaPoco, you're allowed to do transaction management doing something like this:</p>
  
  <pre><code>var newObject = new NewObject();
  var newObjectId = 1;
  using (var scope = db.GetTransaction())
  {
      newObject = db.SingleOrDefault&lt;NewObject&gt;("SELECT * FROM tblNewObject WHERE Id = @0", newObjectId);
      scope.Complete();
  }
  </code></pre>
  
  <p>While this is great for managing when in a transaction updates get committed, it's a little lacking for controlling the isolation level of a transaction similar to how you'd do it with a traditional SQL connection:</p>
  
  <pre><code>TransactionOptions transOptions = new TransactionOptions() { IsolationLevel = IsolationLevel.ReadUncommitted };
  using (new TransactionScope(TransactionScopeOption.Required, transOptions))
  {
      //here be transactions
  }
  </code></pre>
  
  <p>In PetaPoco, <a href="https://github.com/toptensoftware/PetaPoco/blob/master/PetaPoco/PetaPoco.cs#L276">GetTransaction</a> returns a new Transaction, which, using that <a href="https://github.com/toptensoftware/PetaPoco/blob/master/PetaPoco/PetaPoco.cs#L2158">specific constructor</a>, calls <a href="https://github.com/toptensoftware/PetaPoco/blob/master/PetaPoco/PetaPoco.cs#L288">BeginTransaction</a>. BeginTransaction in this case, uses .NET's <a href="https://msdn.microsoft.com/en-us/library/system.data.idbconnection.begintransaction%28v=vs.110%29.aspx">IDbConnection.BeginTransaction()</a> - which has an overload to provide a transaction isolation level. As far as I can tell, PetaPoco does not provide any way to provide an isolation level to that method. Does anyone know if it's possible to actually modify the isolation level of PetaPoco without having to dig into the source and add an overloaded constructor that takes isolation level in? I'm happy to do that and submit a pull request, but I want to make sure before I do the work, I'm not missing something straightforward.</p>