Fix bad javadoc
[PAXWEB-550] Remove superfluous errors when unregistering a web app

Conflicts:
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/UnregisterWebAppVisitorWC.java
Align slf4j usage

Conflicts:
	pax-web-jetty/pom.xml
	pom.xml
[PAXWEB-552] Make servlet context handler have a more meaningful display name
Conflicts:
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/WebAppHttpContext.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/HttpServiceContext.java

Conflicts:
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/HttpServiceContext.java
	pax-web-runtime/src/main/java/org/ops4j/pax/web/service/internal/DefaultHttpContext.java
[PAXWEB-551] Shutting down web applications does not correctly clean objects
Conflicts:
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/Activator.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/HttpServiceContext.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/JettyServerWrapper.java
	pax-web-runtime/src/main/java/org/ops4j/pax/web/service/internal/Activator.java
Conflicts:
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/UnregisterWebAppVisitorWC.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/Activator.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/HttpServiceContext.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/JettyServerImpl.java
	pax-web-jetty/src/main/java/org/ops4j/pax/web/service/jetty/internal/JettyServerWrapper.java
	pax-web-runtime/src/main/java/org/ops4j/pax/web/service/internal/Activator.java
	pax-web-runtime/src/main/java/org/ops4j/pax/web/service/internal/Executor.java
[PAXWEB-549] Concurrency issues with the war extender

Conflicts:
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/Activator.java
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/WebAppPublisher.java
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/WebEventDispatcher.java
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/WebXmlObserver.java
	pax-web-extender-war/src/main/java/org/ops4j/pax/web/extender/war/internal/model/WebApp.java