Fix 7-Zip installers

[scottcopus]

Please fix the 7-Zip installers so they clean up and don't add duplicates to Programs and Features:

cheers,
Scott

[ip7z]

7-zip supports exe installer and msi installer:
7-Zip (x64) is exe installer.
7-Zip (x64 edition) is msi installer.

msi installer works via special msi installing "magic", and we can't control all things related to msi installing. It's controlled by Windows.

exe installer works directly with main windows API. So we control most actions during exe installing.

If we install exe installer over installed msi-7-zip, it
changes only files, but it doesn't change registry things, because registry things from msi installer are complicated.

We recommend to use exe installer only instead of msi installer.
If 7-zip-msi was installed already, and you want to install exe version of installer, you can uninstall 7-zip-msi before installing new exe installer.

[scottcopus]

Can I make a suggestion to maybe add "msi" to the uninstall title in addition to (or in place of) "edition"? The current title makes it hard to know this. It doesn't have to be "msi" but as long as it matches up to something indicating it's an MSI-type installer by also looking at the Download page (https://7-zip.org/download.html), that would be great.

Great software!