CV code; preliminary checks and unit tests

To build, run in ``native/recog``:

* ``mkdir build; cd build``
* ``cmake ..; cmake --build .; ctest``

You should see

```
Test project /Users/janmachacek/Eigengo/akka-patterns/native/recog/build
    Start 1: recog-test
1/1 Test #1: recog-test .......................   Passed    0.06 sec

100% tests passed, 0 tests failed out of 1

Total Test time (real) =   0.06 sec
```