microG Settings integration, icon/activity changes

[Nanolx]

Follow up for #765

• separates launcher icon from main activity (so it can be disabled without making microG inaccessible, think of Launchers that don't allow to hide Apps on their own)
• fix issue #758 (launcher icon not shown on all devices)
• #719 added 'microG settings' to System Settings > Device, move into System Settings directly (result may vary, depending on the ROM and Android Release)
• improved version of the microG icon for System Settings

[Vavun]

Hello @Nanolx

Maybe you can find time to update this pull request? A lot of things have changed.

[Nanolx]

I'll have a look at it next week.

[ghost]

Did this slip through the cracks? This would be super nice to have 👀

[ILoveOpenSourceApplications]

@Nanolx, I don't know if you're free to be able to look into this right now or not. But if possible, it'll be much appreciated. Sorry if I bothered you.

[ale5000-git]

This PR is obsolete because most of its stuff is already merged separately in microG.

[ILoveOpenSourceApplications]

Ah, I see you took it into your own hands and did #2042 & #2061. I did check for any similar PRs, but didn't check thoroughly, my bad. But then, why leave this open still, given that it's obsolete now?

Edit: On a similar note, is #1489 also obsolete?

[ale5000-git]

How I have said "most of its stuff is already merged separately in microG" but probably there is still a small part that isn't, but it need to adapted to the latest code of microG and I don't have time currently.

About #1489 probably yes since the icon of microG got changed in the meantine but I don't have time to check carefully the PR now.