Add Beachball to Repo #2

[pkanher617]

How it works:

1. Developer creates a PR that affects X packages.
2. The "Beachball Check" workflow will check whether the developer has committed changefiles, and will fail and prevent merging if it does not detect them.
3. The developer run "npm run beachball:change" at the root of the repo locally on their PR branch and describes the changes to each affected package. Beachball will generate changefiles and commit them to the branch. The developer should push these changefiles and merge them when the PR is approved.
4. Changefiles are collected on dev. When all the files are ready to be published, a PR to master is created. On merge, the beachball publish command is run, which reviews the changefiles for the highest order release (i.e. major, minor, patch), then bumps the package versions and their dependency versions accordingly, and finally performs the publish.

[coveralls]

Coverage remained the same at 81.794% when pulling 64d2105 on beachball-config into 5c8d98e on dev.

[tnorling]

One question but approved! Excited for this!

[tnorling]

Is there a way to ignore the samples folder completely so we don't have to add this to every sample?

[pkanher617]

I wanted to use the path config but beachball is currently overwriting the path config parameter with cwd so until they fix their config we need to do this.

[tnorling]

Got it. Makes sense

[pkanher617]

I opened a ticket here: microsoft/beachball#377

[sangonzal]

Would be nice to have a description of what the release process looks like after this is merged in, as it's hard to deduce from the config files.

We should also be careful going forward to always include this

{
    "shouldPublish": false
}

into any samples.

[pkanher617]

Example of what is added to the changelog for a minor version change:

## 1.4.0

Fri, 07 Aug 2020 21:42:47 GMT

### Minor changes

- updating files for automated release steps ([email protected])

[sangonzal]

Looks good.