Add nodes/libraries versions matrix in releases

[jpraynaud]

Issue

In order to provide a clear overview of the Mithril nodes version released with a distribution, we need to list the embedded versions of the nodes/libraries in the release.

This can be done:

• In a markdown table as part of the release descrition
• In an artifact file (dedicated to that purpose or in the Version file)

The result could be something like:

Crate	Version
mithril-aggregator	0.1.1
mithril-client	0.2.1
mithril-core	0.1.0
mithril-common	0.1.1
mithril-signer	0.1.1