Fix compiler warnings

Fix some warnings about tasks needing to be awaited.

Author: mrward

src/MonoDevelop.PowerShell/MonoDevelop.PowerShell.Debugging/PowerShellThreadBacktrace.cs

@@ -115,7 +115,7 @@ ObjectValue GetTopLevelScopesObjectValueAsync (StackFrame frame, EvaluationOptio
 			var value = ObjectValue.CreateEvaluating (updater, path, ObjectValueFlags.EvaluatingGroup);
 			value.Name = GettextCatalog.GetString ("Scopes");
 
-			updater.UpdateVariableScopes (path, frame.Address);
+			updater.UpdateVariableScopes (path, frame.Address).Ignore ();
 
 			return value;
 		}

src/MonoDevelop.PowerShell/MonoDevelop.PowerShell.Debugging/PowerShellVariableObjectValueSource.cs

@@ -92,7 +92,7 @@ ObjectValue GetVariableObjectValuesAsync ()
 			var value = ObjectValue.CreateEvaluating (updater, path, ObjectValueFlags.EvaluatingGroup);
 			value.Name = GettextCatalog.GetString ("Variables");
 
-			updater.UpdateVariables (path, variablesReference);
+			updater.UpdateVariables (path, variablesReference).Ignore ();
 
 			return value;
 		}

src/MonoDevelop.PowerShell/MonoDevelop.PowerShell/PowerShellTextEditorExtension.cs

@@ -182,7 +182,7 @@ void UpdateFindReferences (CommandInfo info)
 		void FindReferences ()
 		{
 			var finder = new PowerShellReferencesFinder (Editor, session);
-			finder.FindReferences (fileName, Editor.CaretLocation);
+			finder.FindReferences (fileName, Editor.CaretLocation).Ignore ();
 		}
 
 		[CommandUpdateHandler (EditCommands.Rename)]
@@ -195,7 +195,7 @@ void UpdateRename (CommandInfo info)
 		void Rename ()
 		{
 			var renamer = new PowerShellReferencesFinder (Editor, session);
-			renamer.RenameOccurrences (fileName, Editor.CaretLocation);
+			renamer.RenameOccurrences (fileName, Editor.CaretLocation).Ignore ();
 		}
 
 		public override Task<ParameterHintingResult> HandleParameterCompletionAsync (