Fixes in CHANGES.

CHANGES

@@ -35,7 +35,7 @@ Added [has_default_reduction] to the incremental API.
 
 2015/10/23:
 Modified the meaning of --canonical to allow default reductions to take
-place. There implies no loss of precision in terms of lookahead sets,
+place. This implies no loss of precision in terms of lookahead sets,
 and should allow gaining more contextual information when a syntax
 error is encountered. (It should also lead to a smaller automaton.)
 
@@ -60,7 +60,9 @@ Additions to the incremental API.
 A [supplier] is a function that produces tokens on demand.
 [lexer_lexbuf_to_supplier] turns a lexer and a lexbuf into a supplier.
 [loop] is a ready-made made main parsing loop.
-[loop_handle] is a variant of [loop] that lets the user do her own error handling.
+[loop_handle] is a variant that lets the user do her own error handling.
+[loop_handle_undo] is a variant that additionally allows undoing the last
+  few "spurious" reductions.
 [number] maps a state of the LR(1) automaton to its number.
 
 2015/10/16: