update readme

README.md

@@ -73,7 +73,8 @@ Name | Mandatory | Type | Description
 --- | --- | --- | ---
 **value** | Yes | Class | Full Qualified Name of Java class
 **alias** | No | String | Assign a new name to exported class in typescript
-**export** | No | boolean | if **true**, other than typescript declaration adds definition in file *`-types.ts`. **It is need for instantiable classes, in order  to use `new` operator or factory method(s)**
+**export** | No | boolean | If **true**, other than typescript declaration adds definition in file *`-types.ts`. **It is need for instantiable classes, in order  to use `new` operator or factory method(s)**
+**functional** | No | boolean | If **true** other than typescript declaration adds a **particular** definition. Valid only for interfaces that have one abstract method and haven't `@FunctionalInterface` annotation
 
 **Example**
 ```Java
@@ -96,6 +97,8 @@ Name | Mandatory | Type | Description
   @Type(value=java.net.URI.class, export=true),
   @Type(java.net.URL.class),
 
+  @Type(java.lang.Runnable.class, functional=true)
+
 })
 package org.mypackage;
 ```