add tests interfaces as examples in the doc ; remove unused test binaries ; some code formating

eo/src/eoFunctor.h

@@ -60,6 +60,8 @@ public :
     /// tag to identify a binary function in compile time function selection @see functor_category
     struct binary_function_tag {};
 };
+/** @example t-eoFunctop.cpp
+ */
 
 /**
     Basic Function. Derive from this class when defining