Fix #1679: "0x" was taken as a valid integer literal.
Fixes the tokenizer, tokenize.py and int() to reject this.
Patches by Malte Helmert.
diff --git a/Misc/NEWS b/Misc/NEWS
index a19a8ad..8a6ca66 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,8 @@
 Core and builtins
 -----------------
 
+- Issue #1679: "0x" was taken as a valid integer literal.
+
 - Issue #1865: Bytes as an alias for str and b"" as an alias "" were
   added.