Spring Boot 2.0 (#721)

* Migration to Boot 2.0.

Signed-off-by: Kai Zimmermann <kai.zimmermann@microsoft.com>

hawkbit-runtime/hawkbit-update-server/pom.xml

@@ -51,10 +51,6 @@
          <artifactId>hawkbit-boot-starter</artifactId>
          <version>${project.version}</version>
       </dependency>
-      <dependency>
-         <groupId>org.springframework.boot</groupId>
-         <artifactId>spring-boot-starter-actuator</artifactId>
-      </dependency>
       <dependency>
          <groupId>com.h2database</groupId>
          <artifactId>h2</artifactId>