Deprecate Lexer.unread because of hard to fix newline counting problems

We don't use Lexer.unread anywhere, so it's not worth putting in the
effort to fix this properly.

src/main/java/org/sablecc/sablecc/lexer/Lexer.java

@@ -593,6 +593,12 @@ public class Lexer
         }
     }
 
+    /**
+     * @deprecated This method doesn't restore line/column info correctly in some cases
+     *     (if a token begins in the middle of a CRLF newline pair).
+     *     There is no planned replacement.
+     */
+    @Deprecated
     protected void unread(Token token) throws IOException
     {
         String text = token.getText();

src/main/resources/org/sablecc/sablecc/lexer.txt

@@ -292,6 +292,12 @@ Macro:LexerBody
         }
     }
 
+    /**
+     * @deprecated This method doesn't restore line/column info correctly in some cases
+     *     (if a token begins in the middle of a CRLF newline pair).
+     *     There is no planned replacement.
+     */
+    @Deprecated
     protected void unread(Token token) throws IOException
     {
         String text = token.getText();