Add instructions to README.md for the release process.

Author: jeffbaker

README.md

@@ -23,3 +23,21 @@ For a full build, including unit tests you can run the following
 ```
 ./mvnw clean package
 ```
+
+### Releases
+1. Decide what kind of version bump is necessary, based on [Semantic Versioning](http://semver.org/) conventions.
+In the items below, the version number you select will be referred to as `x.y.z`.
+2. Update the [pom.xml](https://github.com/ExpediaDotCom/haystack-client-java/blob/master/pom.xml),
+changing the version element to `<version>x.y.z</version>`. Note the *removal* of the `-SNAPSHOT` suffix.
+3. Update the
+[ReleaseNotes.md]((https://github.com/ExpediaDotCom/haystack-client-java/blob/master/ReleaseNotes.md))
+file with details of your changes.
+5. Create a pull request with your changes.
+6. Ask for a review of the pull request; when it is approved, the Travis CI build will upload the resulting jar file
+to the [SonaType Staging Repository](https://oss.sonatype.org/#stagingRepositories).
+This will cause the jar file to be released to the 
+[SonaType Release Repository](https://oss.sonatype.org/#nexus-search;quick~haystack-client-java).
+7. Now you have to *put back* the -SNAPSHOT that you removed in step 2. When you do that, bump the `z` value to `z + 1`
+to minimize the chance of somebody trying to release on top of the x.y.z version you just released. Note that the next
+release might not use `x.y.z+1`; it could instead be `x.y+1.0` or `x+1.0.0`
+8. Create another pull request with the change from step 7 and get it merged.