v6.0.0-rc.15

Features

• Server: Update to 6.0 APIs and support Controls (#11680)

Bug Fixes

• Addon-Storysource: Fix broken source when there's no story (#11679)
• Angular: Use system path when checking if asset is a directory (#11472)
• Composition: Fix composition of older storybooks (#11673)
• Core: Fix existing behavior with story prefixes (#11660)
• Core: Fix webpack recursion in mainjs glob processing logic (#11647)

Maintenance

• Addon-knobs: Move @types/react-color to devDeps (#11690)

Dependency Upgrades

• Bump react-docgen-typescript-plugin to 0.5.2 (#11658)