travis: use build stages and publish release automatically

.travis.yml

@@ -1,11 +1,9 @@
 language: go
-go_import_path: github.com/getamis/istanbul-tools
 sudo: required
-os: linux
-dist: trusty
 go:
-  - 1.7.6
-  - 1.8.3
+  - 1.7
+  - 1.8
+  - 1.9
 env:
   - TEST=unit
   - TEST=istanbul
@@ -20,15 +18,33 @@ install:
 
 script:
   - 'if [ ${TEST} = "unit" ]; then
-         travis_wait 30 go test -v $(glide novendor | grep -v "\.\/tests\/\.\.\.") --timeout 30m;
-     elif [ ${TEST} = "istanbul" ]; then
-         cd ${TRAVIS_BUILD_DIR}/tests/functional && travis_wait 120 ginkgo -r --progress;
-     elif [ ${TEST} = "quorum" ]; then
-         cd ${TRAVIS_BUILD_DIR}/tests/quorum && travis_wait 120 ginkgo -r --progress;
-     else
-         echo "Invalid env"
-         exit 2;
-     fi'
+      travis_wait 30 go test -v $(glide novendor | grep -v "\.\/tests\/\.\.\.") --timeout 30m;
+    elif [ ${TEST} = "istanbul" ]; then
+      cd ${TRAVIS_BUILD_DIR}/tests/functional && travis_wait 120 ginkgo -r --progress;
+    elif [ ${TEST} = "quorum" ]; then
+      cd ${TRAVIS_BUILD_DIR}/tests/quorum && travis_wait 120 ginkgo -r --progress;
+    else
+      echo "Invalid env"
+      exit 2;
+    fi'
+branches:
+  only:
+    - develop
+
+jobs:
+  include:
+    - stage: release
+      go: 1.9
+      if: tag =~ ^v
+      env:
+        - TEST=none
+        - REV="$TRAVIS_TAG"
+      deploy:
+        provider: releases
+        api_key: "$GITHUB_OAUTH_TOKEN"
+        skip_cleanup: true
+        on:
+          tags: true
 
 notifications:
   webhooks: