added a returnAll parameter in withPipeline allowing to return all the results of the pipeline in order (syncAndReturnAll) or only those assigned to variables (sync). The latter remains the default

The change is not breaking since the parameter is optional and its default value of false ensures that the previous behavior is kept when the parameter is not passed
Merge pull request #22 from germanSancho/patch-1

added a returnAll parameter in withPipeline allowing to return all the results of the pipeline in order (pipeline.syncAndReturnAll()) or only those assigned to variables (pipeline.sync()). The latter remains the default