Trim the README and polish the display selection

The settings-storage paragraph goes back to the one sentence it was. The screen list now shows native resolutions rather than the scaled ones, the Turkish tab is named Ekran, and the repositioning comment says what a named screen changes.

dikte/overlay.py

@@ -246,7 +246,10 @@ class Overlay(QWidget):
         self.resize(width, HEIGHT)
 
     def _reposition(self):
-        # On a multi-monitor setup, show up where the user actually is.
+        # The screen the settings name, or, when none is named or it is not
+        # plugged in right now, where the user actually is. Names are connector
+        # names on X11 and model names on macOS, where two identical monitors
+        # can share one; the first then wins.
         screen = next(
             (item for item in QApplication.screens() if item.name() == self.screen_name),
             None,