Improve dependency mapping to include coordinates

This commit improves the dependency mapping infrastructure to include the
groupId and artifactId attributes alongside the existing version. For
consistency, the attribute has been renamed from `versions` to
`mappings`.

This allows to better support the `redis` use case: the starter was
renamed from `spring-boot-starter-redis` to
`spring-boot-starter-data-redis` and previously we had two entries
excluding each other using version ranges.

Closes gh-219

initializr-service/application.yml

@@ -91,7 +91,7 @@ initializr:
           groupId: org.projectlombok
           artifactId: lombok
           description: Java annotation library which help to reduce boilerplate code and code faster
-          versions:
+          mappings:
             - versionRange: "[1.2.0.RELEASE,1.4.0.M1)"
               version: 1.16.6
           starter: false
@@ -153,7 +153,7 @@ initializr:
           description: Document RESTful services by combining hand-written and auto-generated documentation
           groupId: org.springframework.restdocs
           artifactId: spring-restdocs-mockmvc
-          versions:
+          mappings:
             - versionRange: "[1.2.0.RELEASE,1.3.0.RC1)"
               version: 1.0.1.RELEASE
           scope: test
@@ -243,7 +243,7 @@ initializr:
           description: PostgreSQL jdbc driver
           groupId: org.postgresql
           artifactId: postgresql
-          versions:
+          mappings:
             - versionRange: "[1.2.0.RELEASE,1.3.0.M1)"
               version: 9.4-1201-jdbc41
           scope: runtime
@@ -269,11 +269,13 @@ initializr:
         - name: Redis
           id: data-redis
           description: REDIS key-value data store, including spring-redis
-          versionRange: 1.4.0.M1
-        - name: Redis
-          id: redis
-          description: REDIS key-value data store, including spring-redis
-          versionRange: "[1.1.5.RELEASE,1.4.0.M1)"
+          aliases:
+            - redis
+          mappings:
+            - versionRange: 1.4.0.M1
+              artifactId: spring-boot-starter-data-redis
+            - versionRange: "[1.1.5.RELEASE,1.4.0.M1)"
+              artifactId: spring-boot-starter-redis
         - name: Gemfire
           id: data-gemfire
           description: GemFire distributed data store including spring-data-gemfire