evlib#rtpath#ExtendVersionedRuntimePath(): 'TODO:' comment (possible bug)
test: EVLibTest_RunUtil_Command_RunTests(): first implementation

 * EVLibTest_RunUtil_Command_RunTests():
  * first crude implementation:
   * unix only;
   * error handling (files not present, failed executions) not reported
      (but noticed);
  * implements:
   * command EVTestRunFiles:
    * options: '-?' (help), '-p PROGRAMS' (to run the tests);
  * automatic help text generation;
  * options aliases ('-p' == '--program' == '--programs');
  * code should be relatively easy to refactor into separate functions:
   * argument parsing (not quite like 'getopts', but not too bad,
      either);
   * automatic help text generation;
   * "run the tests" functionality;