Create activity API

[chamerling]

The monitoring will be able to receive simple activities, store them and list them. An activity can be defined as a high level log message. Examples of activities are:

• Component Lifecycle (start, stop, shutdown, maintenance, ...)
• Errors (triggered by monitoring, governance, components, ...)
• TBC

The activity API will be JSON/REST based with a generic format like:

{
  name: "foo",
  timestamp: "377494774949",
  component: "DSB",
  uuid: "93939-93939-6363-9372",
  context : {
    foo : "bar",
    bar : "foo"
  }
}