Add 1.3 release date

As of http://blog.rust-lang.org/2015/09/17/Rust-1.3.html
2015-09-18 09:19:20 +02:00 · 2015-09-18 09:19:20 +02:00 · da059a4e28
parent cff0411706
commit da059a4e28
1 changed files with 1 additions and 1 deletions
--- a/RELEASES.md
+++ b/RELEASES.md
@ -1,4 +1,4 @@
-Version 1.3.0 (September 2015)
+Version 1.3.0 (2015-09-17)
 ==============================

 * ~900 changes, numerous bugfixes