Ubuntu software center does not show License information for PowerShell package

[raghushantha]

[andyleejordan]

To support this, we'll need to create our own debian/copyright file and include in during package generation with the --deb-meta-file argument to FPM.

There are likely other files and settings we need to configure for every package manager before we release packages into upstream repositories (and we may even want to move away from FPM and instead script every build ourselves).

Note that this is not a problem for going public; we include our license files in the base directory; this is more a matter of presentation.

[andyleejordan]

As this is a packaging aesthetic and not a requirement, moving assignment to @raghushantha.