v0.7.0

The desire to introduce some general API improvements led to dropping the adaptor interface in favor of a traits interface:

• Reducing template argument duplication.
• Removing awkward constructor requirement for metrics.
• Improving interfacing with individual points. E.g.: An OpenCV point required wrapping in v0.6.0.

Changes:

• Updated metrics.
  • Renamed all C++ metrics. Most notable: MetricL2 changed to L2Squared.
  • Python enum entry L2 renamed to L2Squared.
  • Added the L2 metric for C++.
  • Metrics should now be default constructible instead of having a constructor that takes run-time dimensions.
• KdTree construction speed improved by about 5-10% depending on the input size.
• Added pico_understory. It contains a pre-alpha version of an implementation of the cover tree. It won't be added to pico_tree.
• Renamed pico_common to pico_toolshed.
• Adaptor interface requirements for point sets and points replaced by a single traits interface.
  • Added support for working with an std::vector<Point>.
  • Added support for working with an std::reference_wrapper<std::vector<Point>>.
  • Eigen adapter interface updated to a traits interface.
  • Eigen support for std::vector<Eigen::Matrix<>> and std::vector<Eigen::Map<>> added.
  • Eigen support for std::reference_wrapper<Eigen::Matrix<>> added.
• Split the benchmark into multiple benchmarks.
• Split various pico_tree internals into separate files.
• Added an OpenCV interfacing demo.