Rewrite show_my_ip() for Freebsd, extract more infomation of network interfaces, not tested yet.
Add show_my_ip() for Linux, extract more infomation of network interfaces, not tested yet
Add show_my_ip() for Cygwin, extract more infomation of network interfaces, Python2/Python3 tested
Add argument ``all`` for show_my_ip() to filter out interfaces which has no IP address
Change main() output
FreeBSD tested, fixed bug of space/tab
Linux Mint tested, ready to merge into branch ``master``
Refactored version, not compatible with earlier version