Update README.md with clearIfNoMatch option.

Author: MarcoGiancarli

README.md

@@ -74,6 +74,10 @@ When activating the plugin, you may include an object containing options for the
 
  `renderLimit`: The maximum number of suggestions to render on the screen at one time. Useful for dealing with source elements with items.
 
+ `clearIfNoMatch`: When true, the combobox will clear its contents when unfocusing if a matching option is not selected. Defaults to true.
+ 
+ 
+
 
 ## Dependencies
 Uses the latest 1.X version of jQuery and the latest 2.X or 3.X of bootstrap.