Updated "run_test_launcher.bat" to use current WinPython distro (from %WINPYDIRBASE% env var)

Author: PierreRaybaut

run_test_launcher.bat

@@ -1,18 +1,13 @@
 @echo off
-
 setlocal
 set PYTHONPATH=%cd%
-
-for /f %%f in ('dir /b c:\w*') do (call :test %%f)
-pause
-
-exit /B %ERRORLEVEL%
-
-:test
-set ENV=C:\%~1\scripts\env.bat
-if exist %ENV% (
-    echo ************************** Testing with %~1 **************************
-    call %ENV%
-    python -m qwt.tests.__init__
+if defined WINPYDIRBASE (
+    call %WINPYDIRBASE%\scripts\env.bat
+    @echo ==============================================================================
+    @echo:
+    @echo Using WinPython from %WINPYDIRBASE%
+    @echo:
+    @echo ==============================================================================
+    @echo:
     )
-exit /B 0
+python -m qwt.tests.__init__