Added additional logging settings

Author: AndyButland

16/umbraco-cms/reference/configuration/loggingsettings.md

@@ -13,7 +13,9 @@ The following configuration is available in the Logging settings:
   "CMS": {
     "Logging": {
       "MaxLogAge": "2.00:00:00",
-      "Directory": "~/CustomLogFileLocation"
+      "Directory": "~/CustomLogFileLocation",
+      "FileNameFormat": "UmbracoTraceLog.{0}..json",
+      "FileNameFormatArguments": "MachineName"
     }
   }
 }
@@ -30,3 +32,22 @@ To increase the maximum age of the entries in the audit log to 48 hours (2 days)
 By default, all log files are saved to the `umbraco/Logs` directory. You can define a custom directory for your log files by using the `Directory` key in the Logging settings.
 
 Set the value to `~/LogFiles` to add all log files to a `LogFiles` directory in the root of the file structure.
+
+## FileNameFormat
+
+The default file name format for the Umbraco log file is `UmbracoTraceLog.{0}..json`. The single argument is replaced at runtime with the server's machine name.
+
+If you want to change the file name or include additional arguments, you can amend the format with this setting.
+
+## FileNameFormatArguments
+
+By default the single argument for the log file format name is the server's machine name.
+
+Other or additional arguments can be provided via this setting as a comma delimited string:
+
+- `MachineName` - the server's name.
+- `EnvironmentName` - the ASP.NET environment name such as "Development" or "Production.
+
+So for example, to provide both supported arguments you would configure `MachineName,EnvironmentName`.
+
+The number of arguments provided should match the placeholders in the configured `FileNameFormat`.