Fix bug I created during merge from Python-idle.

Also, decided IDENTCHARS is better as global, after all.
diff --git a/Lib/idlelib/PyShell.py b/Lib/idlelib/PyShell.py
index 29ebd92..3a819a8 100644
--- a/Lib/idlelib/PyShell.py
+++ b/Lib/idlelib/PyShell.py
@@ -28,6 +28,8 @@
 import rpc
 import RemoteDebugger
 
+IDENTCHARS = string.ascii_letters + string.digits + "_"
+
 # XX hardwire this for now, remove later  KBK 09Jun02
 use_subprocess = 1 # Set to 1 to spawn subprocess for command execution
 
@@ -313,8 +315,6 @@
         linecache.cache[filename] = len(source)+1, 0, lines, filename
         return filename
     
-    IDENTCHARS = string.ascii_letters + string.digits + "_"
-    
     def showsyntaxerror(self, filename=None):
         """Extend base class method: Add Colorizing