v0.10.0 — Artifact downloads

Added

• Pipeline.artifact() helper to get artifacts for the pipeline instance.
• Pipeline.console_output() helper to get the console output from jobs
  that has finished for a pipeline.

Changed

• Pipeline.instance() now returns the latest instance when counter
  is falsey.
• Pipeline.schedule() has a new argument, return_new_instance which
  will return the new instance that was scheduled. The instance information is
  taken from the Pipeline.history() call and matches the last entry there.