Control module upgrade / Signal Expressions

Major revision of the control module. Introduces broccoli signal expressions to build signal processing chains.

New Features

• [control]:
  • Added Signal class and operators for signal expressions
  • Added time-discrete IIR Filter implementation
  • IIR-based filters now support nth filter output derivative computation
  • Added essential feedback control patterns
  • Extended Wrench constructors
• [core]:
  • Added type traits for initialization of complex data types with zero
• [memory]:
  • Adds CircularAccessor to view linear data structures as circular data

Bug Fixes

• [control]: GaussianNoise is now truely deterministic

Non-Breaking Changes

• [toolchain]:
  • Broccoli now uses the C++14 standard, effectively dropping support for QNX Neutrino < 7.0
  • Improved doxygen layout to support module descriptions

Breaking Changes

• [control]:
  • Reimplemented filters, operators, sources and kinematics to use the Signal API
  • Moved LinearFader to operators and redesigned its API
  • Moved StatisticsEstimator to core module
  • Removed ActivatableModule
  • Moved Wrench and SignalLimits to control main folder
  • SignalLimits now only stores min/max values