[Pharo-project] SystemNavigation with environment

Hi all, I committed SLICE-Issue-00001-MakeSystemNavigationEnvironmentAware-LucFabresse.2 in PharoTaskForces. Now SystemNavigation is environment aware. There two test classes : - SystemNavigationTest has been modified to test SystemNavigation on Smalltalk globals - SystemNavigationOnNewlyCreatedEnvironmentTest tests SystemNavigation on a new Environment have look at SystemNavigationOnNewlyCreatedEnvironmentTest>>testEnsureDefaultEnvironmentNotUsed ClassFactoryWithOrganizationForTestCase has been added to easily create classes ClassFactoryWithOrganizationForTestCaseTest test this latter class. Merge well in 12218 and tests are green. #Luc