Shan't notify for new updates on Linux

[es20490446e]

The app shan't notify for new updates on Linux, as that's already done by the package manager itself.

[Konfekt]

At least the check could be made optional, thus also leaving the configuration file intact.

[es20490446e]

Why? If the package manager already notifies that?

[Konfekt]

Distributions might lag behind, but, personally, yes, I would be fine with dropping the check (in particular, since the config file could be tracked by git). This suggestion is a matter of backwards compatibility.

[es20490446e]

Or just make newer versions ignore the variable.