Set username for S/R commits if provided (#424)

Before this change, we set the username in the mercurial.ini file only when a
repo was cloned. There are situations where we want to pass the `user`
option to a Send/Receive process as well.

+semver:minor

Author: rmunn

src/LfMergeBridge/LanguageForgeSendReceiveActionHandler.cs

@@ -167,6 +167,8 @@ void IBridgeActionTypeHandler.StartWorking(IProgress progress, Dictionary<string
 			syncOptions.RepositorySourcesToTry.Clear(); // Get rid of any default ones, since LF only sends off to the internet (Language Depot).
 			// We use the generic creation code here to make testing easier. In the real world we will only create "HttpRepositoryPath".
 			syncOptions.RepositorySourcesToTry.Add(repositoryAddress);
+			var user = options.ContainsKey(LfMergeBridgeUtilities.user) ? options[LfMergeBridgeUtilities.user] : null;
+			if (user != null) hgRepository.SetUserNameInIni(user, progress);
 
 			progress.WriteVerbose("Syncing");
 			var syncResults = synchronizer.SyncNow(syncOptions);