TravisCI not building on every commit

The planned workflow for releasing into Amazon S3 was:

1. Run `bin/release -v 4.3.0`
  a. Runs `grunt`
  b. Updates `package.json` version to 4.3.0
  c. Runs `npm shrinkwrap` to freeze dependencies
  d. Commits
  e. Tags as `4.3.0`
  f. Deletes `npm-shrinkwrap.json`
  g. Commit deleted npm-shrinkwrap to continue development on master
2. Push both master and the 4.3.0 tag

The issue is that the push that includes both the tagged version with the npm-shrinkwrap.json and the deletion of npm-shrinkwrap.json results in one build on the latest commit, rather than both commits being packaged. It's possible travis has 1-build-per-push semantics rather than 1-build-per-commit, which means we may need to do it in separate pushes to ensure a build gets kicked off for each.

Hopefully it's not intermittent (e.g., depends on whenever the worker picks up the change) but I suspect it might be, and we'll have to find a different production release workflow (e.g., build and release off a branch).