Added support for A12 devices (and added the forgotten source code for iOS 12 :P)

iOS 11 support

*Added an option to add estimated time to the exact time.
Example: "48m ago • 09:41"

*Added an option to add minutes to "Xh ago"
Example: "5h 47m ago"

*You can also combine these two options to get something like this: "5h 47m ago • 09:41"

*Added an icon to the preferences.