Have perl-build.mk resolve to build-depend on libmodule-build-perl if not using Build::Module::Tiny (perl 5.19.0 onwards won't provide it).
Prepare for release: Update changelog.
Fix broken syntax in python-sugar.mk. Urgency=high as this affects packages getting auto-removed from testing.
Prepare for release: Update changelog.
Have debhelper.mk install CONTRIBUTORS and CREDITS as documentation files by default.
Corrected a typo in the VCS URL.
Fix preserve compiler flags set using DEB_* environment variables, in langcore.mk. Closes: bug#712729. Thanks to Simon Ruderich, Emilio Pozuelo Monfort and Markus.
Prepare for release: Update changelog.
Tidy snippets: wrap+strip wide lines.
Introduce new expansion variables cdbs_uc cdbs_lc.
Fix python-distutils.mk and python-sugar.mk to use unversioned runtime for default flavor.
Modernize python-distutils.mk installdir handling (since supported even in oldstable now): Use --install-layout=deb (and drop --prefix=/usr) by default, and use --install-lib option (not --install-purelib/--install-platlib, and only when DEB_PYTHON_DISTUTILS_INSTALLDIR_SKEL is set).  Deprecate cdbs_expand_python_distutils_installdir, and have it provide .../dist-packages dir (not .../site-packages) by default to try cope with packages relying on it for non-skel use. Closes: bug#565973. Thanks to Matthias Klose and Piotr Ożarowski.
Fix error message to talk about multiple python implementations (not packaging systems).
Tidy python-vars.mk: Add/improve comments.
Tidy python-vars.mk: Reorder variables to list legacy before modern, and cdbs_curpkg-resolved last.
Deprecate DEB_CONFIGURE_SCRIPT_ENV, to allow better override control over related variables through its successor, cdbs_autotools_configure_env.
Rename cdbs_python_pysupport → cdbs_pythonsystem_pysupport, and deprecate the former.
Rename cdbs_python_pycentral → cdbs_pythonsystem_pycentral, and deprecate the former.
Rename cdbs_python2 → cdbs_pythonsystem_python2, and deprecate the former.
Rename cdbs_python3 → cdbs_pythonsystem_python3, and deprecate the former.