Add the releases based on tag (#840)

diff --git a/.travis.yml b/.travis.yml
index d5f60b9..08ff498 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -61,6 +61,7 @@
 - export RELEASE_PKG_FILE="$(cd "$TRAVIS_BUILD_DIR/release" && ls ${zip_file_name}-*.tgz ${zip_file_name}-*.zip)"
 - echo "Deploying $RELEASE_PKG_FILE to GitHub releases."
 - export GIT_TAG="latest"
+- export TAG=false
 - if [ "$TRAVIS_BRANCH" == "master" ] && [ "$TRAVIS_EVENT_TYPE" == "push" ] && [ "$TRAVIS_OS_NAME" == "linux" ] ; then
       git config --global user.email "builds@travis-ci.com";
       git config --global user.name "Travis CI";
@@ -71,6 +72,7 @@
   fi
 - if [ ! -z "$TRAVIS_TAG" ] ; then
       export GIT_TAG=$TRAVIS_TAG;
+      export TAG=true
   fi
 - echo "The GIT_TAG of this Travis build is $GIT_TAG."
 
@@ -88,6 +90,7 @@
   tag_name: $GIT_TAG
   on:
     repo: apache/incubator-openwhisk-wskdeploy
+    tags: $TAG
     condition: "$DEPLOY_BUILD_READY = true"
 - provider: script
   skip_cleanup: true