readme update

README.md

@@ -1,16 +1,34 @@
 # Umbraco Nullable Types
 Property editors (and value converters) to enable a null value to be selected in preference to a default value.
 
+## _Nullable String_
+'But strings are always nullable !' however with a textbox alone there's no way to distinguish between whitespace and null, 
+so this data-type adds a checkbox to toggle between the textbox value and a null.
+
+The raw values are stored as json, but will also read in raw string values (as stored by the built-in textstring data-type, so can migrate away from this, but not return if item has been saved).
+The property-value-converter will return a string.
+
+
+### Property Editor
+
+![Property Editor Example](docs/NullableStringPropertyEditor.png)
+
+### Property Editor Configuration
+
+![Property Editor Configuration Example](docs/NullableStringPropertyEditorConfiguration.png)
+
+
 ## _Nullable Boolean_
 A tri-state data-type where the default value is null.
 
 The raw values are stored as strings: "", "0" or "1", which makes it compatable with the built-in true/false data-type.
 The property-value-converter will return a nullable bool.
 
-## _Nullable String_
-'But strings are always nullable !' however with a textbox alone there's no way to distinguish between whitespace and null, 
-so this data-type adds a checkbox to toggle between the textbox value and a null.
+### Property Editor
+
+![Property Editor Example](docs/NullableBooleanPropertyEditor.png)
+
+### Property Editor Configuration
+
+![Property Editor Configuration Example](docs/NullableBooleanPropertyEditorConfiguration.png)
 
-The raw values are stored as json, but it will also read in string values as stored by the built-in textstring data-type 
-(so can migrate away from textstring, but not return if item has been saved).
-The property-value-converter will return a string.