Bintrees

* Use ``sortedcontainers`` instead: https://pypi.python.org/pypi/sortedcontainers
* Project Status: Inactive
* removed official Python 2 support

* BUGFIX: foreach (pure Python implementation) works with empty trees
* acquire GIL for PyMem_Malloc() and PyMem_Free() calls

* BUGFIX: correct deepcopy() for tree in tree

* support for copy.deepcopy()
* changed status back to `Mature`, there will be: bugfixes, compatibility checks and simple additions like this deep
copy support, because I got feedback, that there are some special cases in which `bintrees` can be useful.
* switched development to 64bit only & MS compilers - on Windows 7 everything works fine now with CPython 2.7/3.5/3.6

Repository moved to GitHub: https://github.com/mozman/bintrees.git

* removed logging statements on import
* added helper function bintrees.has_fast_tree_support()
* HINT: pypy runs faster than CPython with Cython extension

* replaced print function by logging.warning for import warning messages
* KNOWN ISSUE: unable to build Cython extension with MingW32 and CPython 3.5 & CPython 2.7.10