Feature: add first version of test logging

Ok as we discussed the following changes need to be made...

[x] Type annotations are needed for Reporter class and all new code
[x] Reporter should be declassified as singleton
[x] Reporter should have a simplified output message such as [PASS|BUILD|TEST_NAME]
[x] Reporter needs to be called after each stage of test batches, rather than after each individual test
[x] Reporter should write test results to JSON formatted log file
[x] Runtime should have option to load existing report file, and print readable results of previous tests

martinruefenacht / lemonspotter