Add chmod 744 for the script file and fix image tag

The primary purpose of this pull request is to update the permission of the script file, /home/gridftp/globus-connect-personal.sh. Dockerfile states it, but 744 was not applied in the image file, leading to a container-starting error.

In globus-connect.yaml, the image tag is added as some nodes pulled the old image which does not have the script file.

In the README.ME, export is added for the environment variables, ep and epkey.