README-publish

The release can be validated with this project:  https://github.com/testng-team/release-validator

To publish:

- ./gradlew bintrayUpload will upload the release to JCenter. It will fail if the version is a SNAPSHOT
- ./gradlew uploadArchives will upload
  - the snapshot to https://oss.sonatype.org/content/repositories/snapshots
  - the release to https://oss.sonatype.org/service/local/staging/deploy/maven2
For a release, you then need to go to https://oss.sonatype.org/index.html#stagingRepositories to manually close and release the distribution.

Notes:

- `./gradlew uploadArchives` is run by Travis after each new push to deploy the latest HEAD to the snapshot directory. As such, the version number of `build.gradle` in the git repo should always be -SNAPSHOT.
- The latest gpg no longer creates `secring.gpg`, but you can generate one with `gpg --export-secret-keys -o ~/.gnupg/secring.gpg`
- The ID of the key is the last eight hex numbers of the key
- You should have a `~/.gradle/gradle.properties`:

```
signing.keyId=<KEY ID, 8 hex numbers>
signing.password=
signing.secretKeyRingFile=<PATH TO secring.gpg>
```
- Make sure to use Gradle 5.0 because later releases will issue a "duplicate key" error when running
`./gradlew uploadArchives`
- If you generate a new key with `gpg --gen-key`, you can then upload it with:
`gpg --send-keys --keyserver keyserver.ubuntu.com $GPGKEY`