Consolidate release script

[cbialorucki]

Proposed changes

• Move Dockerfile to project root
• Move scripts to a new "Scripts" folder
• Use set -euo pipefail instead of || exit 1 on most lines
• Get the release name from git.
• Use "rls" instead of "release" in the file name of deliverables (TODO: Do we still want this?)
• Test for internet connection, if it fails disable parts of the script that require an internet connection.
• Work out of a git clone in /reactos directory instead of /work
• Put deliverables in a separate folder (good if we want more deliverables in the future for different architectures)
• Consolidate script a ton, only needing to git checkout {branch} and running release to build all deliverables
• Update README.md
• Have the Docker image pull scripts from the local repository rather than downloading from git (so you can work on the image locally easier)
• Probably more I forgot

[learn-more]

overall lgtm, some minor points.

[learn-more]

Do you want to do some validation on the format of the name?

[learn-more]

This means that you can never build an older release?

[learn-more]

You might want to include errors like no internet / no optional modules here.