add a basic readme

README.md

@@ -0,0 +1,36 @@
+# release-plan
+
+This package was originally developed to help release [Embroider](https://github.com/embroider-build/embroider) and was extracted so everyone can use it 🎉
+
+## Installation
+
+```
+npm i --save-dev release-plan
+```
+
+## Usage
+
+To use `release-plan` you need to have a valid `GITHUB_AUTH` environment variable that has the `repo` permission. This allows `release-plan` to check what PRs have been merged since the last release and plan the release accordingly.
+
+1. Run `npx release-plan explain-plan`. If there are unlabeled PRs that need to be released it will complain and show you a list of them. Each PR needs to be labeled with one of: 
+    - breaking
+    - enhancement
+    - bug
+    - documentation
+    - internal
+
+2. Once all the PRs are labeled, `release-plan` will instead show you the release plan, explaining which packages are getting released, at which versions, and why.
+
+3. If you disagree with the plan, you can modify the list of changes before using it to `explain-plan` or `prepare` a release:
+
+    - `npx release-plan gather-changes > /tmp/changelog`
+    - edit `/tmp/changelog`
+    - `npx release-plan --from-stdin < /tmp/changelog`
+
+    For example, this can be necessary if a PR that's labeled `breaking` touches multiple packages and only one of those packages is actually a breaking change. In that case you can take the other package names out of the description of the PR.
+
+4. Once you're happy with the plan, run `npx release-plan prepare`. This will edit CHANGELOG.md, bump the version numbers in package.json files, and create a file named `.release-plan.json`. Make a PR with these changes.
+
+5. Once the PR is merged, in a clean local repo at the merge commit, run `npx release-plan publish`. if you need an `otp` for your release you can provide that to the `publish` command like this `npx release-plan publish --otp=123456`
+
+