Added
- initial work for benchmark tests
Changed
- sped up emit and general flow of points through longer pipelines, exact numbers
will be monitored by the new benchmark tests
- added implicit sink when one isn't provided so running something like:
`flume "emit(limit=1)"` still produces output on the CLI. The default is to
set the implicit_sink value on the execute() method to None so that pipelines
can be executed that have no sink programatically