implemented support for remarks in new translator

added new getCommands() to get commands from the input line (for now
just one command) allowing for the (first) command to be a REM command
or ' operator (RemOp) and for a command to be terminated by a ' (RemOp);
the Rem or RemOp token is appended to the rpn output list and the next
token is obtained (which will be an EOL token)

renamed getCommand() to processCommand() and modified it to be passed
the first token (usually a command token except for assignments) instead
of it getting the first token itself

updated results for test #15 (rem tests) for changes in the translation
of PRINT and INPUT statements (old results saved)