#1509 - Migrate to main branch.

Move all project references to `main` instead of `master`.

Jenkinsfile

@@ -154,7 +154,7 @@ pipeline {
 		stage('Release documentation') {
 			when {
 				anyOf {
-					branch 'master'
+					branch 'main'
 					branch 'release'
 				}
 			}

README.adoc

@@ -2,7 +2,7 @@ image:https://spring.io/badges/spring-hateoas/ga.svg[link=https://spring.io/proj
 image:https://spring.io/badges/spring-hateoas/snapshot.svg[link=https://spring.io/projects/spring-hateoas]
 image:https://badges.gitter.im/spring-projects/spring-hateoas.png[link=https://gitter.im/spring-projects/spring-hateoas]
 
-image:https://jenkins.spring.io/buildStatus/icon?job=spring-hateoas%2Fmaster&subject=master[link=https://jenkins.spring.io/view/SpringHATEOAS/job/spring-hateoas/]
+image:https://jenkins.spring.io/buildStatus/icon?job=spring-hateoas%2Fmain&subject=main[link=https://jenkins.spring.io/view/SpringHATEOAS/job/spring-hateoas/]
 image:https://jenkins.spring.io/buildStatus/icon?job=spring-hateoas%2F1.2.x&subject=1.2.x[link=https://jenkins.spring.io/view/SpringHATEOAS/job/spring-hateoas/]
 image:https://jenkins.spring.io/buildStatus/icon?job=spring-hateoas%2F1.1.x&subject=1.1.x[link=https://jenkins.spring.io/view/SpringHATEOAS/job/spring-hateoas/]
 image:https://jenkins.spring.io/buildStatus/icon?job=spring-hateoas%2F1.0.x&subject=1.0.x[link=https://jenkins.spring.io/view/SpringHATEOAS/job/spring-hateoas/]

src/main/asciidoc/mediatypes.adoc

@@ -895,7 +895,7 @@ The preferred way to implement media type representations is by providing a type
 In the `Serializer` and `Deserializer` implementations registered for `RepresentationModel`, convert the instances into the media type-specific model types and then lookup the Jackson serializer for those.
 
 The media types supported by default use the same configuration mechanism as third-party implementations would do.
-So it's worth studying the implementations in https://github.com/spring-projects/spring-hateoas/tree/master/src/main/java/org/springframework/hateoas/mediatype[the `mediatype` package].
+So it's worth studying the implementations in https://github.com/spring-projects/spring-hateoas/tree/main/src/main/java/org/springframework/hateoas/mediatype[the `mediatype` package].
 Note, that the built in media type implementations keep their configuration classes package private, as they're activated via `@EnableHypermediaSupport`.
 Custom implementations should probably make those public instead to make sure, users can import those configuration classes from their application packages.
 

src/main/asciidoc/migrate-to-1.0.adoc

@@ -39,7 +39,7 @@ Also the name changes have been reflected in the classes contained in `TypeRefer
 [[migrate-to-1.0.script]]
 == The migration script
 
-You can find https://github.com/spring-projects/spring-hateoas/tree/master/etc[a script] to run from your application root that will update all import statements and static method references to Spring HATEOAS types that moved in our source code repository.
+You can find https://github.com/spring-projects/spring-hateoas/tree/main/etc[a script] to run from your application root that will update all import statements and static method references to Spring HATEOAS types that moved in our source code repository.
 Simply download that, run it from your project root.
 By default it will inspect all Java source files and replace the legacy Spring HATEOAS type references with the new ones.