6.0.0: Major dependency upgrade

• Added PHP 8.5 to test matrix - @thekid
• Dropped support for older dependency versions - @thekid

5.3.0: Parallel request handling

• Merged PR #33: Refactor OAuth flows to handle parallel requests - @thekid

5.2.1: State reuse fix

• Fixed OAuth2 implementation to redirect to the correct target URL when
  reusing state from a previous authorization flow.
  (@thekid)

5.2.0: Session namespaces

• Merged PR #31: Make it possible to change the session namespace (CAS)
  (@thekid)
• Merged PR #30: Make it possible to change the session namespace (OAuth)
  (@thekid)

5.1.0: Mutable callback and scopes

• Merged PR #29: Make callback and scopes mutable - @thekid

5.0.0: PHP 7.4+, address library

• Dropped support for PHP 7.0 - 7.3, step 1 of xp-framework/rfc#343
  (@thekid)
• Merged PR #28: Refactor CAS authentication flow to use address library
  (@thekid)

4.2.0: XML library compatibility

• Made compatible with xp-framework/xml 12.0+ - @thekid

4.1.0: XP 12 compatibility

• Made compatible with XP 12 - @thekid

4.0.0: Drop XP <= 9

• Implemented xp-framework/rfc#341: Drop XP <= 9 compatibility - @thekid
• Heads up: Removed deprecated Token class which has been replaced
  by web.auth.oauth.BySecret
  (@thekid)

3.8.0: Library compatibility

• Added PHP 8.4 to the test matrix - @thekid
• Made this library compatible with xp-forge/web version 4.0 - @thekid