* Change port index in port_config.ini to 1-based
* Add default port index to port_config.ini, change platform plugins to accept 1-based port index
* fix port index in sfp_event.py
( All device-specific files now reside under /device directory in a <vendor-name>/<platform-string>/<hardware-SKU> directory structure in repo.
* Device-specific files are now packaged into a Debian package (sonic-device-data) and are now installed to /usr/share/sonic/device/<platform-string>/<hardware-SKU>/ directory on switch.