Pointer cleanup (#242)

- Made greater use of smart pointers, eliminating many instances of manual memory management
- Do not use pointers at all for many non-polymorphic classes
- Assorted other code cleanup

backends/merge/Record.cpp

@@ -26,32 +26,6 @@ namespace glabels
 	namespace merge
 	{
 
-		///
-		/// Constructor
-		///
-		Record::Record() : mSelected( true )
-		{
-		}
-
-
-		///
-		/// Constructor
-		///
-		Record::Record( const Record* record )
-			: QMap<QString,QString>(*record), mSelected(record->mSelected)
-		{
-		}
-
-
-		///
-		/// Clone
-		///
-		Record* Record::clone() const
-		{
-			return new Record( this );
-		}
-
-
 		///
 		/// Is record selected?
 		///