[master] Update classification document to match the debug output

The debug output was modified to output text strings using
single quotes instead of double quotes but the document missed
getting this update.

ChangeLog

@@ -1,3 +1,8 @@
+1120.	[bug]		sar
+	Update the classification document to match the output from
+	the debug statements.
+	(Trac NA, git TBD)
+
 1119.	[func]		sar
 	Add debug logging to the classification tokens.  This uses
 	the loggers "kea-dhcp4.eval" and "kea-dhcp6.eval" to capture

doc/guide/classify.xml

@@ -695,12 +695,12 @@
      The logging might then resemble this:
        <screen>
        2016-05-19 13:35:04.163 DEBUG [kea.eval/44478] EVAL_DEBUG_OPTION Pushing option 61 with value 0x666F6F626172
-       2016-05-19 13:35:04.164 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string "0"
-       2016-05-19 13:35:04.165 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string "3"
+       2016-05-19 13:35:04.164 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string '0'
+       2016-05-19 13:35:04.165 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string '3'
        2016-05-19 13:35:04.166 DEBUG [kea.eval/44478] EVAL_DEBUG_SUBSTRING Popping length 3, start 0,
        string 0x666F6F626172 pushing result 0x666F6F
-       2016-05-19 13:35:04.167 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string "foo"
-       2016-05-19 13:35:04.168 DEBUG [kea.eval/44478] EVAL_DEBUG_EQUAL Popping 0x666F6F and 0x666F6F pushing result "true"
+       2016-05-19 13:35:04.167 DEBUG [kea.eval/44478] EVAL_DEBUG_STRING Pushing text string 'foo'
+       2016-05-19 13:35:04.168 DEBUG [kea.eval/44478] EVAL_DEBUG_EQUAL Popping 0x666F6F and 0x666F6F pushing result 'true'
        </screen>
      </para>