Use sender_email in sftpclient
Fix bug where port number is set to NoneType, even if one is provided in site-catalog.xml in site_URI for GSM
Change makefile to use the default folders `gsm-devconfig/gsmi-devconfig`
Help devs to get config data
Remove unused gsm properties "send_email", "receiver_email" from `setup.json`
Merged changes from upstream/develop