Allow Actions to return results (Result Object in ActionResponse).

Adds an Object result field to ActionResponse, so Actions can store
a result there.
The field is intended to hold the result of the execution
when execution has finished successfully, and should be null otherwise.
Even when an action has been executed successfully, its result may be null.
Merge pull request #644 from isartcanyameres/feature/action-returns

Feature/action returns
DOSGi version upgraded to 1.5.0. It solves ConcurrentModificationException's executing OpenNaaS.
Merge pull request #649 from logoff/issue/dosgi-exception

DOSGi version upgraded to 1.5.0.
Define and implement OFProvisioningNetworkCapability.

FlowIds are randomly generated UUIDs.

TODO: obtain result from ActionResponse and return it in capability methods.
Merge branch 'develop' into feature/of-net-model
OFProvisioningNetworkCapability getAllocatedFlow method returns result taken from action response.
Define SDNNetworkInternalActionsetImplementation providing an (empty) implementation for OFProvisioningNetworkActionSet.
Register sdnnetwork bundle in parent pom
ITest for sdnnetwork being correctly published.
Merge pull request #658 from isartcanyameres/feature/of-net-provision-capab

Feature/of net provision capab