fixes the updating process bug related with #91

[ttuygun]

Fixes #91

The default updating URL depends on https://objective-see.com/products.json but it's no longer up-to-date in contrast with github. For this reason, I changed the updating url as github using github's public API. I also changed objectForKey methods according to new URL.

Here's the working example. In this example, I'm on 1.1.0 and program says 1.1.1 is available.

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[jonathancross]

@ttuygun you need to sign the CLA and rebase, otherwise this can't be merged. (I don't know if it will be merged though)

[jamesalfei]

Is there any way we can get this PR progressed at all? Even if it means closing this PR and getting another contributor (like myself) to raise the changes? It seems the author is not active on this project at all.

[mdjunior]

Hi,
Analyzing the history of the issues repository, I think that not using the Github API is intentional.
In other words, it is expected that there will be version control outside of Github so that the latest versions of Github will only be made available to users after some testing period here. By putting LuLu to read directly from Github, we would be exposing people who want a stable version to new features that may not have been well tested yet.

#402 (comment)