function?associateFiles（action?userExtList?fileStr）

%?associateFiles（action?extList?fileStr）
%
%?Makes?a?registry?files?that?can?be?used?to?set?correct?file?associantions?on
%?a?windows?platform.?The?following?MATLAB?file?extensions?are?supported:
%?.m?.mat?.fig?.mexw32?.mexw64?.p?.mdl?.mdlp?.slx?.mldatx?.req
%?.sldd?.slddc?.slxp?.sltx?.mn?.mu?.muphlp?.xvc?.xvz?.ssc?.mlapp
%?.mlappinstall?.mltbx?.mlpkginstall?.mlprj
%
%?INPUT:
%?action??-?optional?string.?
%???????????*?‘add‘?（default）?adds/rewrites?the?MATLAB?file?association?registry
%??????????????keys?for?this?version.
%???????????*?‘delete‘?deletes?the?MATLAB?file?association?registry?entries?for
%??????????????ALL?versions?of?MATLAB?（including?“old?style“?ones）
%???????????*?‘deleteadd‘?i