* Add ffmpeg buildpack for scalingo.
* Add environment variable to install ffprobe
Note: For existing applications, admins needs to add 'WITH_FFPROBE=true' to environment variable.
* Allow SMTP auth method customization
* Add SMTP openssl_verify_mode option support
Allows one use self-signed certs with their SMTP server.
* Add SMTP enable_starttls_auto option support