[KARAF-2756] Define an annotation for completers and retrieve them from the OSGi Service Registry
[KARAF-2756] Use @Completer for config commands
[KARAF-2756] Use @Completer for feature commands
[KARAF-2756] Use @Completer for instance commands
[KARAF-2756] Use @Completer for kar commands
[KARAF-2756] Use @Completer for jaas commands
[KARAF-2756] Allow simple StringsCompleter definitions using @Completer
[KARAF-2756] Use @Completer for log commands
[KARAF-2756] Fix @Completer to correctly handle multi-valued arguments
[KARAF-2756] Hide Completer services
[KARAF-2756] Use @Completer for jdbc commands
[KARAF-2756] Use @Completer for jms commands
[KARAF-2756] Use @Completer for jndi commands
[KARAF-2756] Use @Completer for service commands
[KARAF-2756] Use @Completer for shell commands