Refactore activemq layout and remove Spring dependency

The idea is to refactor ActiveMQ, removing Spring dependency.

The layout will be:

• activemq-broker-boot is inspired from Karaf Minho and loading the beans without Spring
• activemq-broker-api is the interfaces allowing to manipulate broker
• activemq-broker-model loads the model with pluggable loaders, supporting xml, json, yaml model definition
• activemq-broker-server is the implementation binding the model and API all together. It's loaded by the boot runtime.
• activemq-client* for the client face (pool, client, ...)