Extend the unit testing framework to allow test to compare results with expected results that are stored in separate files:

• Instead of using ASSERT_EQ test should be allowed to write to ostream, and after completion the output will be compared against the known output from a resource file.
• In case of difference, test should fail with the diff. Also a temp file with actual out put should be created to allow for investigation or bulk diffing.
• Add tooling to update the expected output files based on actual result. Should support bulk update if all changes to expected results are desired.

 Depends on https://jira.mongodb.org/browse/SERVER-62736 to be able to allow inclusion of expected output files into the target binary, so that the contents can be used for comparison.