add information about rsetup version

[onlineapps-cloud]

hi, why you don't show version of this tool? you have great place in about page to put it!
apt list --installed rsetup this is not friendly, and not all users know about this command!

[RadxaYuntian]

The version info is not part of the source code but the package code, so there is no straight forward way to embedded this information.

I also don't think user should care about their rsetup version that much. We publish the latest version on our own package repository, so it is not like Debian where the user is stuck with a specific version for the whole distro release. When in doubt just do a system update, and that will get you the latest version of rsetup.