Add optional description field for output report

[alexcasalboni]

This could be as simple as an optional "description" or "notes" field in the state machine intput, that will be passed as is to the state machine output, mainly to explain the context/configuration of the power-tuning execution.

[dougtoppin]

Including the note/description in the results page would be useful. This allows a record of what the conditions of the test were without having to refer back to the execution output.
An example would be if the payload for the Lambda might refer to large or small data to be processed

[alexcasalboni]

@dougtoppin then it's a job for https://github.com/matteo-ronchetti/aws-lambda-power-tuning-ui (plus some integration code in the analyzer.js function).

So far, I've been hesitant to add too much information to the visualization page to avoid issues related to privacy. That page doesn't need any sensitive/confidential information to be rendered (Account IDs, ARNs, etc.).

A generic description isn't necessarily sensitive, but it could contain confidential information. In that case, organizations might become more careful with sharing those public visualization URLs.

Thoughts?