Only upload nightly if on master branch

scripts/circle-test.sh

@@ -87,6 +87,11 @@ elif [ -n "${PACKAGE}" ]; then
     # install boto & rpm (packaging & AWS dependencies)
     exit_if_fail sudo apt-get install -y rpm python-boto
     unset GOGC
+    if [ "$(git rev-parse --abbrev-ref HEAD)" = master ]
+    then
         exit_if_fail ./scripts/build.py --nightly --package --platform=all --arch=all --upload --bucket=dl.influxdata.com/telegraf/nightlies
+    else
+        exit_if_fail ./scripts/build.py --package --platform=all --arch=all
+    fi
     mv build $CIRCLE_ARTIFACTS
 fi