Allow hotfixing by pushing to hotfix/*

Also push tags when we deploy to npm

.travis.yml

@@ -4,6 +4,8 @@ node_js:
 env:
   global:
   - NODE_ENV=production
+  - NPM_TAG=latest
+  - RELEASE_TIMESTAMP="$(date +'%Y%m%d%H%M%S')"
   matrix:
   - NPM_SCRIPT="unit"
 cache:
@@ -21,9 +23,18 @@ jobs:
     - stage: release
       env: NPM_SCRIPT=build
       before_deploy:
-      - npm --no-git-tag-version version 0.2.0-prerelease.$(date +%Y%m%d%H%M%S)
-      - git config --global user.email $(git log --pretty=format:"%ae" -n1)
-      - git config --global user.name $(git log --pretty=format:"%an" -n1)
+      - >
+        if [ -z "$BEFORE_DEPLOY_RAN" ]; then
+          VPKG=$($(npm bin)/json -f package.json version)
+          export RELEASE_VERSION=${VPKG}-prerelease.${RELEASE_TIMESTAMP}
+          npm --no-git-tag-version version $RELEASE_VERSION
+          if [[ "$TRAVIS_BRANCH" == hotfix/* ]]; then # double brackets are important for matching the wildcard
+            export NPM_TAG=hotfix
+          fi
+          git config --global user.email "$(git log --pretty=format:"%ae" -n1)"
+          git config --global user.name "$(git log --pretty=format:"%an" -n1)"
+          export BEFORE_DEPLOY_RAN=true
+        fi
       deploy:
       - provider: script
         on:
@@ -39,17 +50,30 @@ jobs:
         script: npm run --silent deploy -- -x -a -r https://${GH_TOKEN}@github.com/${TRAVIS_REPO_SLUG}.git
       - provider: npm
         on:
-          branch: develop
+          branch:
+          - master
+          - develop
+          - hotfix/*
           condition: $TRAVIS_EVENT_TYPE != cron
         skip_cleanup: true
         email: $NPM_EMAIL
         api_key: $NPM_TOKEN
+        tag: $NPM_TAG
       - provider: script
         on:
-          branch: develop
-          condition: $TRAVIS_EVENT_TYPE == cron
+          branch:
+          - master
+          - develop
+          - hotfix/*
+          condition: $TRAVIS_EVENT_TYPE != cron
         skip_cleanup: true
-        script: npm run i18n:src && npm run i18n:push
+        script: if npm info | grep -q $RELEASE_VERSION; then git tag $RELEASE_VERSION && git push https://${GH_TOKEN}@github.com/${TRAVIS_REPO_SLUG}.git $RELEASE_VERSION; fi
+    - provider: script
+      on:
+        branch: develop
+        condition: $TRAVIS_EVENT_TYPE == cron
+      skip_cleanup: true
+      script: npm run i18n:src && npm run i18n:push
 stages:
 - test
 - name: release