Add alias for netstat, -p option is useful :)

-p, --programs           display PID/Program name for sockets
Add godir() function stolen from AOSP, and customized for VIVOTEK project development.

0. use $PRODUCTDIR env as default project root.
1. Add a handy feature for godir() to $EDITOR a matched file by "e" option directly.
   Usage: godir <regex> [e]
   btw, you can choose 'a' to edit all matched files
   => Select one ([a] -> all): a
Add for markdown syntax