Improve scala-cli deb package to better follow conventions

[bjornregnell]

Problem

The current deb package of scala-cli version 0.1.12 has these flags:

Package: scala-cli
Maintainer: Scala CLI
Architecture: all
Version: 0.1.12
Description: Scala CLI

But there are several flags missing, including Priority, Section, that are expected in a "normal" deb package, according to our university sysadm.

Solution

Our university sysadm suggests something similar to:

Package: scala-cli
Priority: optional
Section: devel
Maintainer: <preferrably an email address or forum address>
Architecture: all
Version: 0.1.12
Description: Scala CLI

It would also be good if the version is part of the .deb file name so that you can see what version you have downloaded just by looking at the filename.