Add coverage statistics report to logs

[Lana243]

After we run tests with coverage, we can see the following time execution statistics report:

 | __________________________________________________ | ____________ | _______________ | ____________ | 
 |                                           Function | % of overall | Total time (ms) | Times called | 
 | __________________________________________________ | ____________ | _______________ | ____________ | 
 | CoverageAndResultsGenerator.cpp:37        generate |       100.00 |            3393 |            1 | 
 | TestRunner.cpp:135                        runTests |        98.79 |            3352 |            1 | 
 | CoverageAndResultsGenerator.cpp:86 collectCoverage |         0.77 |              26 |            1 | 
 | LlvmCoverageTool.cpp:54        getCoverageCommands |         0.47 |              16 |            1 | 
 | TestRunner.cpp:159                            init |         0.41 |              14 |            1 | 
 | __________________________________________________ | ____________ | _______________ | ____________ | 

It would be helpful to have similar coverage statistics report. As an example, it can help us a lot with creating benchmarks.

[Lana243]

After discussion, it was decided that it would be better to output statistics report in separate file.
The first design of such statistics report is .csv file where one row is statistics for one file.
Statistics should include:

• Time statistics: preparation, generation, execution time.
• Tests execution statistics. Number of compiled, passed, failed, broken tests.
• Coverage info.