Bug-fix: when moving files using the 'R'emove/edit file prompt

(sbbs_t:::listfileinfo), long filenames would be shortened to micros~1
shortened filenames (on Win32 only). This bug was fixed by simply
using the same movefile() function called from the batch flagging
prompt (sbbs_t::batchflagprompt) ,where this bug was already fixed in v3.13a.