Feature proposal: Detect if application (pwa) is installed

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Hi Manu,

What do you think about adding a state and adapt directives which could detect and react (show/hide) if application has been installed on a mobile device or is running in web browser.
I have some uses cases for this and I think I could make a pull request if you want to include it in ngx-responsive. But if you think it doesn't fit here I can still include it in my own project, so it's up to you.

Thanks for this great project.