Fix Python 2.6 incompatibility with remote_tests

[Baguage]

Transferred from redmine, #6344

The remote tests package has the following issues when run with Python 2.6:

When no module names are provided on the command line, the main module attempts test discovery. However, test discovery was introduced in Python 2.7
The TestCase.assertRegexEquals method was also introduced in Python 2.7
These should be fixed so the tests can run on Python 2.6