#577 Change eclipse.org to eclipse.dev

• Changed eclipse.org to eclipse.dev, where relevant. I didn't update the namespace URIs of the metamodels, to ensure models stay backwards compatible. Since eclipse.org stays registered to the Eclipse Foundation, I don't think we need to change this.
• Changed www.eclipse.dev to eclipse.dev. The non-www variant is now the canonical URL, so removed all www. parts for www.eclipse.dev/escet. This also fixes bugs, as for www.eclipse.org/escet/<version> and now www.eclipse.dev/escet/<version>, <version> was not replaced for URLs with www.. For more robustness, now also www. URLs are rewritten.
• Removed an outdated comment in CIF documentation sources.

Most easily reviewed per commit, to see similar changes together.

Addresses #577 (closed)