README: add Adjuster images.

README.md

@@ -2304,6 +2304,11 @@ value changes. This enables dynamic color change.
 ```python
 from gui.widgets.adjuster import Adjuster
 ```
+![Image](./images/adjusters.jpg)  ![Image](./images/adj_vector.jpg)  
+
+Four examples paired with `Label`s. An example of two `Adjuster` instances
+setting a vector.
+
 The `Adjuster` is a space saving version of the `Knob`. It is normally paired
 with a `Label` which provides user feedback of the value. It has a range of
 0.0 to 1.0 and a visual arc of 270°. User code can provide arbitrary scaling

gui/demos/adjust_vec.py

@@ -27,7 +27,7 @@ class BaseScreen(Screen):
         wri = CWriter(ssd, font, GREEN, BLACK)
         col = 2
         row = 2
-        self.dial = Dial(wri, row, col, bdcolor=None)
+        self.dial = Dial(wri, row, col, bdcolor=None, style=Dial.COMPASS)
         self.vec = Pointer(self.dial)
         a = Adjuster(wri, row, self.dial.mcol + 2, fgcolor=BLUE, callback=self.phi_cb)
         Label(wri, row, a.mcol + 2, "ϕ", fgcolor=BLUE)