- actually enabled charset anchors in the engine (still not
  used by the code generator)

- changed max repeat value in engine (to match earlier array fix)

- added experimental "which part matched?" mechanism to sre; see
  http://hem.passagen.se/eff/2000_07_01_bot-archive.htm#416954
  or python-dev for details.
diff --git a/Modules/sre.h b/Modules/sre.h
index 274f085..7e7d835 100644
--- a/Modules/sre.h
+++ b/Modules/sre.h
@@ -33,6 +33,7 @@
     PyObject_HEAD
     PyObject* string; /* link to the target string */
     PatternObject* pattern; /* link to the regex (pattern) object */
+    int index; /* last index marker seen by the engine (-1 if none) */
     int groups; /* number of groups (start/end marks) */
     int mark[2];
 } MatchObject;
@@ -57,6 +58,7 @@
     /* character size */
     int charsize;
     /* registers */
+    int index;
     int lastmark;
     void* mark[SRE_MARK_SIZE];
     /* backtracking stack */