Use DuckDuckGo favicon service (#1073)

* Use DuckDuckGo favicon service

There are multiple ways of how favicon of a website can be published:
- Have a `favicon.ico` file under the website root
- Set through `<link rel="shortcut icon" href="..." />` tag
- Set through `<link rel="icon" href="..." />` tag, or
- Set through platform-specific tags like `<link rel="apple-touch-icon" href="..." />`

Current implementation only supports first option, which does not work in many cases.

Instead of implementing favicon fetching logic from scratch, favicon fetching services can be used.
There are multiple of them, e.g.:
- https://icons.duckduckgo.com/ip3/www.google.com.ico
- https://www.google.com/s2/favicons?domain=www.google.com

This change switched from fetching favicon from the original host to DuckDuckGo.

* Create UX for favicon download method preferences

* Add preferences for favicon download method

* Adjust preferences window location

Also, sort localized resources

Co-authored-by: Alex Rakov <alexander-rakov@users.noreply.github.com>

MacPass/MPGeneralPreferencesController.h

@@ -37,5 +37,6 @@
 @property (strong) IBOutlet NSButton *enableAutosaveCheckButton;
 @property (strong) IBOutlet NSButton *rememberKeyFileCheckButton;
 @property (strong) IBOutlet NSPopUpButton *fileChangeStrategyPopup;
+@property (strong) IBOutlet NSPopUpButton *faviconDownloadMethodPopup;
 
 @end