doc: add properties to sample file

doc/sample/Expressions.im

@@ -47,7 +47,7 @@ while x > 2 do
 end
 
 for i in 0 to:100 step:2 do
-    cout put:"Count is {i}"
+    cout put:'Count is {i}'
 end
 
 cout put:"message" while x > 2.
@@ -108,4 +108,15 @@ class Person
             #days   => self::age / 365,
             _       => 0
         end!
+		
+	$ exampleProperty | get => self::val, set => self::val = value.
+
+    $ exampleProperty2 |
+        get => self::val.
+
+    $ exampleProperty3 | get => 42.
+
+    $ exampleProperty4 (get, set)
+
+    $ exampleProperty5 (get)
 end