* added a randomize flag and corresponding -r command line argument that   allows the caller to execute the various tests in pseudo-random order -   default is still to execute tests in the order returned by findtests().
* added a randomize flag and corresponding -r command line argument that
  allows the caller to execute the various tests in pseudo-random order -
  default is still to execute tests in the order returned by findtests().

* moved initialization of the various flag variables to the main() function
  definition, making it possible to execute regrtest.main() interactively
  and still override default behavior.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator