[All] Fix link bug

zsh/.virtual_env_config.zsh_mac.example

@@ -9,3 +9,7 @@ export WORKON_HOME=~/python-envs
 export VIRTUALENVWRAPPER_VIRTUALENV=$PREFIX/bin/virtualenv
 mkdir -p $WORKON_HOME
 source $PREFIX/bin/virtualenvwrapper.sh
+
+if [ -n "$VIRTUAL_ENV" ] && [[ -f "$VIRTUAL_ENV/bin/activate" ]]; then
+      source $VIRTUAL_ENV/bin/activate;
+fi