* Reading a slice in gather mode is significantly faster
* Use ftello when available to support large files on systems where long is
32-bit
* The python extension is changed to use C++; a C++ compiler is now required,
not just optional, when building the python extension
* Many internal and infrastructure improvements
* The python library is built with setuptools - still integrated with cmake.
Users building from source can still do cmake && make
* Git tag is now authority on version numbers, as opposed to the version string
recorded in the cmake file.
* General building and infrastructure improvements