moved translator output list functions to rpn list class

added new RpnList::append() and RpnList::insert() with code from
Translator::outputAppend() and Translator::outputInsert(), which now
call the new functions, and were left in place for the command translate
functions (the Translator functions call the RpnList functions directly)

moved Translator::outputAssignCodes() to RpnList::setCodeSize() and
removed RpnList::resetCodeSize() and incrementCodeSize() since the code
size variable can now be accessed directly