Make the release note summaries flow directly to marketplace

Currently the release notes are published through a 2 steps procedure:

1. retrieve the information from JIRA and write it to a file misc/releaseNotes.md
2. uploadReleaseNotes.sh reads misc/releaseNotes.md and uploads to the marketplace.

This is due to the previous process where the rephrasing happened in the markdown file.

Now the rephrasing is done directly in JIRA so there is no need to create the misc/releaseNotes.md file.

Moreover the current uploadReleaseNotes script prevents any usage when the temporary branch is gone. This means it not usable once the HF has been released (allowing a typo fix for instance).

Both scripts should be merged and only the upload step in the release job should be kept.

https://github.com/nuxeo/integration-scripts-priv/blob/master/hfBuilder/releaseNotes.sh
https://github.com/nuxeo/integration-scripts-priv/blob/master/hfBuilder/uploadReleaseNotes.sh