Created the ReciprocityPlugin.
The plugin is instatiated with the reference of ManagerController...
The plugin has basicly 3 methods: 
	1 - newRequest: checks if there are enough resources for the new coming
request, and performs the needed resource deallocation when the
requester has higher reputation than other federation member consumer
	2 - linkInstanceToFederationMember: everytime the manager creates a new
instance for a federation member, the plugin adds the instance id to the
list of NofInstances on the correct NofMember
(federation member). NofInstances is composed by an instanceId and the
fCU (calculated with the benchmarking).
	3 - remove: everytime the manager removes/deallocates a local instance
donated to a federation member, the plugin must remove the instance id
from the list of NofInstances on the correct NofMember (federation
member).