Remove Jackson dependency on Version infrastructure

Closes gh-808

initializr-web/src/main/java/io/spring/initializr/web/autoconfigure/InitializrAutoConfiguration.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2018 the original author or authors.
+ * Copyright 2012-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -155,6 +155,11 @@ public class InitializrAutoConfiguration {
 			return new UiController(metadataProvider);
 		}
 
+		@Bean
+		public InitializrModule InitializrJacksonModule() {
+			return new InitializrModule();
+		}
+
 	}
 
 	/**

initializr-web/src/main/java/io/spring/initializr/web/autoconfigure/InitializrModule.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2012-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.spring.initializr.web.autoconfigure;
+
+import java.io.IOException;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.databind.ser.std.StdSerializer;
+import io.spring.initializr.util.VersionProperty;
+
+/**
+ * A {@link SimpleModule} that registers custom serializers.
+ *
+ * @author Stephane Nicoll
+ */
+class InitializrModule extends SimpleModule {
+
+	InitializrModule() {
+		super("initializr");
+		addSerializer(new VersionPropertySerializer());
+	}
+
+	private static class VersionPropertySerializer
+			extends StdSerializer<VersionProperty> {
+
+		VersionPropertySerializer() {
+			super(VersionProperty.class);
+		}
+
+		@Override
+		public void serialize(VersionProperty value, JsonGenerator gen,
+				SerializerProvider provider) throws IOException {
+			gen.writeString(value.toStandardFormat());
+		}
+
+	}
+
+}