PYBIND11 based wrappers

Moved to PYBIND11 for wrapper generation, from the earlier Boost.Python wrappers. PYBIND11 is a header-only library that is much easier to install and has faster compile- and run-time performance than Boost.Python. Also dropped support for Python2 to reduce the maintenance overhead.

Package name update

The Python package name is now updated to itpp (from the earlier py_itpp), as per the convention for Python wrapper libraries. The src/ directory structure, build system, and examples have been updated to incorporate this change. Accordingly, the new way to load the package is simply, "import itpp".

First release.

First release. Validated for Python2 and Python3 in Linux environments. Major contributions span Python API for data structures including vectors and matrices, mathematical operations including Fourier and other transforms, and radio (i.e., wireless) communications support. This release has been extensively utilized for simulations involving radio communication over fading and additive white Gaussian noise channels. Bit interleaving, channel coding, modulation, etc. are supported.