Internal API change

now query & mutation share same base class
queries are now self-refetchable
queryJobs & mutationJobs now support dynamic key allowing dynamic Query/Mutation creation
query status & mutation status are now just on point & accurate

packages/fl_query/lib/fl_query.dart

@@ -3,4 +3,7 @@ library fl_query;
 export 'query.dart';
 export 'query_bowl.dart';
 export 'query_builder.dart';
+export 'mutation.dart';
+export 'mutation_builder.dart';
 export 'models/query_job.dart';
+export 'models/mutation_job.dart';