* Imported Upstream version 2.3.1+ds. * Fix debian/watch to determine new releases by parsing the SVN tags of upstream's version control system. * Update get-orig-source target for new release. * dh_strip override: Replace $VER variable with 2.3.0 string. * debian/copyright: Add new Public Domain and Apache 2.0 license. * libbox2d-dev.install: - Install *.cmake files in /usr/lib/$(DEB_HOST_MULTIARCH)/cmake/Box2D.