added:
SortingStation
RPNCalculator
removed:
class RPNCalculator
class SortingStation

added:
EvaluationMatrix extended for ADDITION_OP

changed:
StateMachineCalculator now parse math expressions onto reverse polish notation commands (to rpnCommands in EvaluationStack),
which means, that their execution will evaluate input math expression.
Executions of revers polish notation commands performing in FINISH state.
SortingStation algorithm development:
evaluation of precedence
SortingStation algorithm development:
precedence
inner parentheses support