v1.4.0

• Enhance heuristic detection capabilities and improve email notification logging
  • Added multiple new spam detection methods including referrer analysis, user agent analysis, content length analysis, mixed script detection, Unicode anomalies detection, numbers/letters only detection, and IP address detection in content.
  • Migrated existing settings from disable_* to enable_* for heuristic checks, ensuring all checks are enabled by default when heuristic detection is activated.
  • Improved email notification logging in the Activity Log to track success/failure status of daily and weekly summary emails.
  • Updated documentation in README.md and README.txt to reflect new features and changes in settings.