move build logic into cmake

[hendrikmuhs]

work in progress

This change removes duplication of build logic and moves most of the logic into cmake. Cmake writes a configuration file which setup.py takes as input to know how to compile/link the library. Apart from that the cmake file has been overhauled to follow best practices.

Notes:

• only tested on linux, likely breaks on OSX

[coveralls]

Coverage decreased (-23.9%) to 71.482% when pulling de4fc81 on hendrikmuhs:build-refactor into f1f2bbf on KeyviDev:master.

[hendrikmuhs]

The decrease in coverage is due to a change in compiler flags, before: -O3 --coverage, after this PR -O0 --coverage, -O3 seems to decrease the number of relevant lines.