Support execution logging using Serilog.

This patch introduces execution logging which is implemented using
Serilog package. The package is new for me but it seems to be
promising. All Information is logged to the Console and all Debug
data is logged into the file.
Fix the path of the accidently removed resource.
Support parallel test execution.

Executing test can take some time. In order to improve the performance
the parallelis was introduced in the application. It is very
important that the parallel execution doesn't affect the measured
times. In order to achieve this goal only CPU - 1 is used and the
left one should be enough to support the operating system.