Add ITK Software Guide to the Insight Journal

Give it a DOI, providing all the associated benefits for their authors.

Also, it could be a good test case of publication with multiple revisions.

Just a proposal, looking forward to hearing your thoughts @thewtex

The issue names no files, tests, or entry points. Start by clarifying how the ITK Software Guide should receive a DOI and how multiple revisions should be represented. Done means the proposal is resolved and the guide has a DOI with revision support.

索引モデルが issue の本文から書いたものです。