ui: rename ops to have Op suffixed, not prefixed

Match Go's FooError name pattern.

While we're here, rename RedrawOp to InvalidateOp.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

ui/input/key.go

@@ -92,7 +92,7 @@ loop:
 		}
 		switch ops.OpType(encOp.Data[0]) {
 		case ops.TypeKeyHandler:
-			var op key.OpHandler
+			var op key.HandlerOp
 			op.Decode(encOp.Data, encOp.Refs)
 			var newPri listenerPriority
 			switch {