code: public static final <X, R extends X> Function<R,Boolean> or(final IFunction<X,Boolean> left, final IFunction<? super R,Boolean> right) {
          return new Or<X,R>(left, right);
      }
docs: <p>
  Takes two boolean functions (<tt>Function&lt;?,Boolean&gt;</tt>) as
  parameters and returns another one which returns true if any of the functions
  returns true, and false if not.
  </p>
  
  @param left the left side of the "or" operation
  @param right the right side of the "or" operation
  @return a function returning true if any of the functions return true, and false if not.