control: align XY/Z origin tile color with other axis tiles

Drop the .ghost class from the XY Origin and Z Origin tiles so they
use the same flat slate color as the X-/X+/Z+ neighbors. The lighter
ghost tone made them look like a different category of action when
they are just origin shortcuts.

src/pug/templates/control-view.pug

@@ -76,11 +76,11 @@ script#control-view-template(type="text/x-template")
 
           // Row 2
           button.jbtn(@click="jog_fn(-1, 0, 0, 0)") X−
-          button.jbtn.ghost(@click="showMoveToZeroDialog('xy')")
+          button.jbtn(@click="showMoveToZeroDialog('xy')")
             span.lbl XY
             span Origin
           button.jbtn(@click="jog_fn(1, 0, 0, 0)") X+
-          button.jbtn.ghost(@click="showMoveToZeroDialog('z')")
+          button.jbtn(@click="showMoveToZeroDialog('z')")
             span.lbl Z
             span Origin