Changes in this release:
* add FreeEEG32 for all OSes
* move to new manylinux image, there is centos 6 and new GCC. Before we used CentOS 5 and GCC 4.8
* Drop support of GCC < 5
* Add support for custom baud rate to Serial class
* Add Serial Number check for Callibri device
Using modern GCC we can also provide compiled C++ libraries for C++ users.
Before there was ABI mismatch between GCC 4.8 and 5.0+