Visual Studio runner displays console output captured per test.
Allow runners to supply their own TextWriter as the target or Console output.  Visual Studio runner provides such a TextWriter in order to redirect all console output to the VS Output window along with other VS Test Adapter output.  Due to severe limitations in the VS Test Adapter API, all such output must be line-buffered and must be prefixed with a nonempty string (in this case "[Console] ".
Merge pull request #70 from plioi/ImproveHandlingOfConsoleCapture

Visual Studio runner redirects all console output to the VS Output window, and reports per-test console output as part of each test result.