use program model for encoder testing

modified program model to store encoded lines temporarily in the line
info list, added a temporary access function for the rpn list (for
access from the tester class), modified debug text function to receive a
line index instead of a pointer to a program word and a word count, and
modified update line function to encode line after a successful
translate and store the encoded line into the line info list (for just
the insert operation)

modified tester class encode input function to let the program model
translate and encode the line, retrieving the rpn list afterward for
output; and removed deleting the rpn list since the program model still
has possession of it

modified tester class run loop to not report token errors after each
line for encoder testing since program model still has the tokens in the
rpn lists; and modified the program model destructor to delete the rpn
lists (a memory leak that previously only showed up when using the gui)