Feat/add gama overhead

[cortze]

Motivation

The simulator gives accurate results, but only when simulating single or sequential operations like one single provide or sequential provides. It doesn't add penalization or extra delay when we want to emulate the performance of many concurrent lookups, provides, or retrievals.

Description

This PR aims to set the basis to emulate the overhead performance of concurrent operations by adding a new argument gamma, which will always aggregate a slight delay to the total duration of the operation.
This way, if we want to emulate 2 parallel lookups with a given connection delay of 20ms and an overhead of 1ms. The connections for the first lookup will have a total of 20ms latency, while the second ones will have 20+1ms

Tasks

• Add Gamma parameter to the DHTNetwork
• unify the ConnectionError and the Connection summary to display the internal connections later on
• add network summary exporter (readable from panda.DataFrames to make fancier plots)
• add Overhead resetter to the DHTNetwork in case we want to emulate multiple concurrent operations
• update tests + add a new one for the gamma parameter

Proof of Success

• Test happy