simplify template based on google-chrome template and remove the redundant INSTALL and REMOVE scripts

[slymattz]

Testing the changes

• I tested the changes in this PR: YES

[ahesford]

The reason this package is so written is so that users can install from a nonfree repo and be notified of updates without tracking them manually. We can't distribute the contents of the package, so we distribute a package that will fetch the contents from the official source at install time.

[slymattz]

Gotcha. Sorry.

BTW is there a way to limit the use of the nonfree repo to just chromium-widevine? I'm talking about some sort of a whitelist.