[iterator.concept.sentinel] Spell "see" with lower-case 's'.

Author: tkoeppe

source/iterators.tex

@@ -1518,7 +1518,7 @@
   concept @\deflibconcept{sentinel_for}@ =
     @\libconcept{semiregular}@<S> &&
     @\libconcept{input_or_output_iterator}@<I> &&
-    @\exposconcept{weakly-equality-comparable-with}@<S, I>; // See \ref{concept.equalitycomparable}
+    @\exposconcept{weakly-equality-comparable-with}@<S, I>;      // see \ref{concept.equalitycomparable}
 \end{itemdecl}
 
 \begin{itemdescr}