Updated Configuration File (markdown)

Configuration-File.md

@@ -18,13 +18,25 @@ When Gaseous-Server is started for the first time, it creates a configuration fi
 | MaxLibraryScanWorkers | maxlibraryscanworkers |        | 4              |
 | HasheousHost | hasheoushost |     | https://hasheous.org/ |
 
+#### Notes
+* MetadataSource is reserved for future use - currently only IGDB is available
+* SignatureSource governs where Gaseous will look for ROM hash signatures (typically from DATs):
+  * LocalOnly (default): sets Gaseous to only look in the local database for DATs. You will need to import the DATs yourself (see: https://github.com/gaseous-project/gaseous-server/wiki/Signatures#local-signatures)
+  * Hasheous: sets Gaseous to also refer to the Hasheous service when attempting to match a signature (see: https://github.com/gaseous-project/gaseous-server/wiki/Signatures#hasheous, and the Hasheous project: https://github.com/gaseous-project/hasheous)
+* MaxLibraryScanWorkers: sets the number of maximum number of workers that Gaseous will use when performing a Library Scan. Each library is allocated one worker to scan it's content. Setting this too high may cause:
+  * server performance issues, and/or
+  * the IGDB API to throttle your connection (IGDB only allows 4 API calls per second)
+* HasheousHost: sets the host that Gaseous will use for the Hasheous service (see: https://github.com/gaseous-project/gaseous-server/wiki/Signatures#hasheous)
+
 ### IGDBConfiguration
 | Attribute | Environment Variable |
 | --------- | -------------------- |
 | ClientId  | igdbclientid         |
 | Secret.   | igdbclientsecret     |
 
-### config.json
+See https://github.com/gaseous-project/gaseous-server/wiki/Metadata#igdb for information on configuring these attributes.
+
+## Example config.json
 ```json
 {
   "DatabaseConfiguration": {