Change the zipimport implementation to accept files containing
arbitrary bytes before the actual zip compatible archive.  Zipfiles
containing comments at the end of the file are still not supported.

Add a testcase to test_zipimport, and update NEWS.

This closes sf #775637 and sf #669036.
diff --git a/Misc/NEWS b/Misc/NEWS
index 7ba1218..af56c77 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,10 @@
 Core and builtins
 -----------------
 
+- It is now possible to import from zipfiles containing additional
+  data bytes before the zip compatible archive. Zipfiles containing a
+  comment at the end are still unsupported.
+
 Extension modules
 -----------------