v0.22

• API Refactoring: Synapse relations are now established through a separate builder class.
• The range positions are now optionally variable. This feature is required for text generation. In this
  use case the positions are not known in advance and need to be computed during processing.
• Introduced passive neurons. Passive neurons are only evaluated if the connected output neuron requires it. Passive neurons act basically like callback functions.
• Optimization of the interpretation search.
• Lots of bug fixes.