showStart variant for when there's no worktree file

Clean up some uses of showStart with "" for the file,
or in some cases, a non-filename description string. That would
generate bad json, although none of the commands doing that
supported --json.

Using "" for the file resulted in output like "foo  rest";
now the extra space is eliminated.

This commit was sponsored by Fernando Jimenez on Patreon.

Command/InitRemote.hs

@@ -38,7 +38,7 @@ start (name:ws) = ifM (isJust <$> findExisting name)
 				let c = newConfig name
 				t <- either giveup return (findType config)
 
-				showStart "initremote" name
+				showStart' "initremote" (Just name)
 				next $ perform t name $ M.union config c
 			)
 	)