Email notification for all create/edit/delete events and logging of some

[geofranzi]

Some instances need more information on certain activities within the system (e.g. download).

Option in settings to activate sending a notification for several events

• make sending mails optional via settings config as not all may want this

Email notification

• data update / append
• data structure create / update
• easy upload
• file /attachment upload / delete
• Dataset download
• Changed email
• Download unstructured

Logging

• download
• ...

Replace/add the user name to mails instead of user account name (if available)

(mandatory for all emails sent to users, but would be also good for all other mails)

• replace account name

[geofranzi]

for logging download or we use READ (not used until now)
add crude state "download"
https://github.com/javadch/VWF.Mvc/blob/eaef78d9096f528f3190b0528b5b8e7ec80daf22/Vaiona.Entities/Logging/LogEntry.cs#L19

add LogDataDownload analog to L123 -143. Add "message" as a parameter for description instead of a predefined string. It will contain later the download format.
https://github.com/javadch/VWF.Mvc/blob/eaef78d9096f528f3190b0528b5b8e7ec80daf22/Vaiona.Logging/LoggerFactory.cs#L123

how to use:
LoggerFactory.LogDataDownload(datasetId.ToString(), typeof(Dataset).Name, Vaiona.Entities.Logging.CrudState.Downloaded, "excel");