Working on #303 (Embed OSGi environment to execute plugins on portal server)

More exports in the system.bundle extension (Guice, RS, SNAA)
Working on #303 (Embed OSGi environment to execute plugins on portal server)

Bridging OSGi Log Service to SLF4J
Working on #303 (Embed OSGi environment to execute plugins on portal server)

Providing Guice module to plugins so the can use DI for their services.
Fixing a bug in PortalEventBus that wouldn't return responses to requests of unconnected nodes if some plugin registered on the PortalEventBus
Added helper class RSHelper that wraps RS and SM and allows to query for reserved or unreserved nodes in a given time interval.
Fixed bug in WisemlProviderConfig that hindered starting up TR without having configured all properties for the WisemlProvider
Closes #302 (Flash default image onto unreserved nodes)

Fully realized as a plugin for TR portal