Allow same WADI Dispatcher to be used across multiple web-app contexts

WadiSessionManager creates itself a WADI Dispatcher instance. The idea of this improvement is to refactor this class so that a Dispatcher is passed in to it so that multiple Web-application contexts can share the same Dispatcher, i.e. group communication infrastructure.

As part of this patch, the version of WADI is moved to 2.0-M5, which provides a basic administration console and some internal changes to the way replication is working (these internal changes are preceding the support of replication at the field or method level of any type of POJOs).