Add a filter to generate a request id

[lmineiro]

Often there is a flow id that helps gather events and log entries from multiple systems originated for the same customer request.

Such flow id needs to be generated at the earliest and sent down the request path so that the following systems can use it for those purposes.

I suggest we use a common HTTP header X-Flow-Id that is created for every request. Generation of this id should favor performance and relax on collision probability since the time window where this is relevant is limited