[WIP] Feature/circleci

[ivigns]

Provided integration of CircleCI.

[code-of-kpp]

So copying file with some lines commented is always a bad idea. But we can start from there. A better thing to do is to add some preprocessor defines, that will disable some features. And, for a minimum setup, disable as many of them as needed to fit the container.
Also it would be great to look at other CI providers, so we can fit there without disabling anything.