Revert "Temporarily disable deploying to Chocolatey (#960)" (#1128)

This reverts commit 01ed720. Now that
google/dart_cli_pkg#56 has landed, Chocolatey deployment should work
again.

.travis.yml

@@ -182,6 +182,20 @@ jobs:
       skip_cleanup: true
       on: {tags: true}
 
+  # Deploy to Chocolatey.
+  - name: Chocolatey
+    if: *deploy-if
+    os: windows
+    env:
+      # CHOCOLATEY_TOKEN="..."
+      - secure: "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"
+    script: skip
+    deploy:
+      provider: script
+      script: pub run grinder pkg-chocolatey-deploy
+      skip_cleanup: true
+      on: {tags: true}
+
   # Redeploy sass-lang.com.
   - name: sass-lang.com
     if: *deploy-if

pubspec.yaml

@@ -34,7 +34,7 @@ dependencies:
 dev_dependencies:
   archive: ">=1.0.0 <3.0.0"
   analyzer: "^0.40.0"
-  cli_pkg: "^1.0.0-beta.10"
+  cli_pkg: "^1.0.0-beta.12"
   crypto: ">=0.9.2 <3.0.0"
   dart_style: "^1.2.0"
   grinder: "^0.8.0"