Modify TROOT::GetClass to return a pointer to the "fake" class created by TStreamerInfo in case the class has no fClassInfo.
Modify TROOT::GetClass to return a pointer to the "fake" class created by TStreamerInfo
in case the class has no fClassInfo.

Philippe has added some protections in TROOT::GetMacroPath in case this function
is called after having changed the environment gEnv.


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@1840 27541ba8-7e3a-0410-8455-c3a389f83636

dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,dawehner/root,bbannier/ROOT,dawehner/root,dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT,bbannier/ROOT