Improve ConsoleListenerTests by including the assembly-level entry and exit text in the asserted console output.  Phases out one usage of deprecated ConventionRunner.
Improve TeamCityListenerTests by including the assembly-level entry and exit text in the asserted console output.  Phases out one usage of deprecated ConventionRunner.
AssertionLibraryFilterTests no longer uses deprecated ConventionRunner.
Change ConventionRunnerTests to RunnerTests, so that it exercises Runner instead of the deprecated ConventionRunner.
Move convention running logic from deprecated ConventionRunner to Runner to enable further refactoring of convention running.