Spring Cloud Release Train is a curated set of dependencies across a
range of Spring Cloud projects. You consume it by using the
spring-cloud-dependencies POM to manage dependencies in Maven or
Gradle. The release trains have names, not versions, to avoid
confusion with the sub-projects. The names are an alphabetic sequence
(so you can sort them chronologically) with names of London Tube
stations ("Angel" is the first release, "Brixton" is the second).