0.4.0

• Added support for first-run setup when no configuration is present.
  • If modpack is not defined, it will ask you to provide url, id or name.
  • If url is provided, it will automatically extract modpack id and optionally the version (if not set, it will ask for it).
  • If id is provided, it will use it to lookup the pack, then require selecting version.
  • Otherwise it will search for the modpack by name, allowing you to select it. After that you need to select the version.
• Improved file downloading. It now uses temporary files before moving them to correct location.
• Improved handling of hashes and old file cleaning. It should now do better job and preserve modified, but not updated files.
• Added support for non SHA-512 hashes. SHA-512 is still used for modpack file validation.
• You can now change version list source by defining version_list_url in modpack-info.json.
• Java version is now checked, preventing usage of versions older than one supported by Minecraft.
• Downgraded GSON to old release to make the jar file smaller (as many new features weren't used anyway).
• Removed some useless / duplicate logs.
• Added support for reading modpack info from bytes prepended to the jar (for example via cat modpack-info.json mrpack4server-X.Y.Z.jar > server.jar) [@vgskye]