move fileExtension to tsg.preference.fileExtension

keep the last tsg extension file in tsg.preference using circshift
tsg.preference.fileExtension = ...
        circshift(tsg.preference.fileExtension, 1 - filterIndex);
update to v1.481

tsg_util/tsg_preferences.m

@@ -137,6 +137,8 @@ return
     preference.char_version          = CHAR_VERSION;
     preference.date_version          = DATE_VERSION;
     preference.autoload              = 'off';
+    preference.fileExtension = ({'*.lbv';'*.nc';'*.arg';'*.ast';'*.btl';'*.ora';...
+      '*.sdf';'*.spl'; '*.transmit*'; '*.tsgqc';'*.xml';'*.cnv'});
     % Climatology
     preference.levitus_version       = {'WOA01','WOA05','ISAS13'};
     preference.levitus_value         = 2;  % WOA05