Partial backport of r78826: leave import site error handler unchanged (print
the error and continue).

Merged revisions 78826-78827 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk

........
  r78826 | victor.stinner | 2010-03-10 23:30:19 +0100 (mer., 10 mars 2010) | 5 lines

  Issue #3137: Don't ignore errors at startup, especially a keyboard interrupt
  (SIGINT). If an error occurs while importing the site module, the error is
  printed and Python exits. Initialize the GIL before importing the site
  module.
........
  r78827 | victor.stinner | 2010-03-10 23:45:04 +0100 (mer., 10 mars 2010) | 4 lines

  ooops, fix error message in execusercustomize()

  Copy/paste failure :-)
........
diff --git a/Lib/site.py b/Lib/site.py
index 21c7db2..66c56c2 100644
--- a/Lib/site.py
+++ b/Lib/site.py
@@ -472,6 +472,12 @@
         import sitecustomize
     except ImportError:
         pass
+    except Exception:
+        if sys.flags.verbose:
+            sys.excepthook(*sys.exc_info())
+        else:
+            print >>sys.stderr, \
+                "'import sitecustomize' failed; use -v for traceback"
 
 
 def execusercustomize():
@@ -480,6 +486,12 @@
         import usercustomize
     except ImportError:
         pass
+    except Exception:
+        if sys.flags.verbose:
+            sys.excepthook(*sys.exc_info())
+        else:
+            print>>sys.stderr, \
+                "'import usercustomize' failed; use -v for traceback"
 
 
 def main():