MC Hub v6.0.0

Added

• Added Puppet provisioning status checking
• Added JupyterHub and FreeIPA links to the UI after a successful provisioning

Removed

• Removed outdated documentation
• Removed unused Idle cluster status code
• Removed build_success status code, replaced with provisioning_* status codes

Fixed

• Fixed Alpine Linux packages version pinning in Dockerfile

Security

• Updated serialize-javascript to v3.1.0
• Updated node-forge to v0.10.0