Samples cleanup

- Modifying dependencies to starter-web with tomcat exclusion plus
  alternative servlet container instead of manual dependency on
  spring-webmvc as it is the preferrable way to use alternative servlet
  container
- Previously RestTemplate with ssl was configured manually in tests - now
  it rellies on autoconfiguration - changed this for multi-connector test
  and added test to ensure that ssl autoconfiguration is working
- Most samples with alterntative servlet containers used some kind of
  service reading property and returning default since it wasn't
  configured - removed it, since it is not specific to using alternative
  servlet containers.

See gh-10548

spring-boot-samples/spring-boot-sample-tomcat-jsp/pom.xml

@@ -27,11 +27,6 @@
 			<artifactId>jstl</artifactId>
 		</dependency>
 		<!-- Provided -->
-		<dependency>
-			<groupId>org.springframework.boot</groupId>
-			<artifactId>spring-boot-starter-tomcat</artifactId>
-			<scope>provided</scope>
-		</dependency>
 		<dependency>
 			<groupId>org.apache.tomcat.embed</groupId>
 			<artifactId>tomcat-embed-jasper</artifactId>