[Maria-developers] Patch for Windows problem with setting TZ

Hi, Alex Budovski has done some work to debug why some tests (binlog tests in particular) are failing on Windows, and found that this is because mysql-test-run.pl set the TZ variable. This interacts poorly with the Windows Operating System. It's actually only a few test cases that need to set TZ. Here is a quick patch that avoids the need to set TZ except for tests that specifically requests it (with the already existing --timezone=XXX mechanism in -master.opt). Opinions? - Kristian.