Spelling fixes, phase 1.

samples/example.cpp

@@ -137,7 +137,7 @@ int main(int /*argc*/, char * /*argv*/[]) {
 
   //To do: Add examples of handling Boxed_Values directly when needed
 
-  //Creating a functor on the stack and using it immediatly 
+  //Creating a functor on the stack and using it immediately 
   int x = chai.eval<std::function<int (int, int)> >("fun (x, y) { return x + y; }")(5, 6);
 
   std::stringstream ss;