tc-testing: Add new TdcResults module

This module includes new classes for tdc to use in keeping track
of test case results, instead of generating and tracking a lengthy
string.

The new module can be extended to support multiple formal
test result formats to be friendlier to automation.

Signed-off-by: Lucas Bates <lucasb@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>