Cloudflare R2

Changed

• Updated requirements for Craft CMS 5 compatibility
• Updated documentation URLs

Fixed

• Prevent calls to GetObjectAcl when copying and moving files (#6)
• Cleanup unused classes

Changed

• Version change since R2 is now generally available
• Updated README.md

Added

• Added $region property (fixes manual bucket selection issue)

Changed

• Replaced instances of Craft::parseEnv() with App::parseEnv()

Removed

• Reverted createAdapter() back to using visibility() method (reverts object visibility to be based on $makeUploadsPublic property)
• Removed Cloudfront-related logic

Initial release