[release-branch.go1.5] go1.5

This updates the VERSION file.
The release proper has not happened yet.

Change-Id: I3e33b5f95aede0da8ca1aef0d9c381942873c9a8
Reviewed-on: https://go-review.googlesource.com/13702
Reviewed-by: Rob Pike <r@golang.org>

VERSION

diff --git a/VERSION b/VERSION
index c548f34..661b4f9 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-go1.5rc1
\ No newline at end of file
+go1.5
\ No newline at end of file