Update php/release.sh to be executable and create a new branch for the new version
diff --git a/php/release.sh b/php/release.sh
old mode 100644
new mode 100755
index 220ca2a..6b0baac
--- a/php/release.sh
+++ b/php/release.sh
@@ -20,7 +20,7 @@
 
 # Checkout the target version
 pushd protobuf/php
-git checkout $VERSION
+git checkout -b $VERSION
 popd
 
 # Copy files