Add enable logs setting for Flat File Import (#7342)

* Add config for enabling Flat File Import logging

* Move logs to default log location for extensions

* Add localized strings

extensions/import/package.nls.json

@@ -0,0 +1,4 @@
+{
+	"flatfileimport.configuration.title": "Flat File Import configuration",
+	"flatfileimport.logDebugInfo": "[Optional] Log debug output to the console (View -> Output) and then select appropriate output channel from the dropdown"
+}