v0.4.7

• Event handling system with zero-crossing detection and handling of scheduled events with error control, compatible with all integrators
• 25% faster AD by using integer indexing for gradient references in Value class
• blocks, connections and events are the three major system components that are managed by the Simulation class now
• blocks, connections and events have on and off methods that enable activating and deactivating them (dynamically, based on events or for debugging purposes) in the simulation