Release 0.2.3

What's Changed

• Metadata for undertow by @mhalbritter in #77
• Update NBT to 0.9.14 by @mhalbritter in #81
• Add thymeleaf-extras-springsecurity6 metadata by @sdeleuze in #80
• Add metadata for org.eclipse.jetty 11.0.12 (rebased) by @sdeleuze in #83

Full Changelog: 0.2.2...0.2.3