New plugin OAUTH2
- Added a detailed SMTP protocol log between client and server for the send mail process for test mails
- Added a filter for the userdefined id in the REST API
- Added a new plugin: OAUTH2 - this allows to get access token via OAUTH2 for the mail notification and HTTP POST process
- Fixed a problem where the event manager reads mail notification templates in other formats than UTF-8 and came back with an error if this wasn't the file encoding
- Modified the W3C schemas for the partner related XML API as the OAUTH2 plugin adds additional configuration options