REST API: Add build and test runs endpoints
As in the title, add 2 new POST endpoints. I've tested it manually and adding both builds and test runs works via script and API.
As for importing test runs via API I've implemented it with the least amount of code changes I had to do. The run_import
module needs some refactor in near future as the code is really coupled.
Related-to: #176 (closed)
Edited by Piotr Kira