make use of to_string function

alib2common/src/core/components.hpp

alib2data/src/alphabet/NonlinearVariableSymbol.cpp

alib2data/src/automaton/FSM/CompactNFA.cpp

alib2data/src/automaton/FSM/DFA.h

alib2data/src/automaton/FSM/EpsilonNFA.cpp

alib2data/src/automaton/FSM/ExtendedNFA.cpp

alib2data/src/automaton/FSM/MultiInitialStateNFA.cpp

alib2data/src/automaton/FSM/NFA.cpp

alib2data/src/automaton/PDA/DPDA.cpp

alib2data/src/automaton/PDA/InputDrivenDPDA.cpp

alib2data/src/automaton/PDA/InputDrivenNPDA.cpp

alib2data/src/automaton/PDA/NPDA.cpp

alib2data/src/automaton/PDA/NPDTA.cpp

...ata/src/automaton/PDA/RealTimeHeightDeterministicDPDA.cpp

...ata/src/automaton/PDA/RealTimeHeightDeterministicNPDA.cpp

alib2data/src/automaton/PDA/SinglePopDPDA.cpp

alib2data/src/automaton/PDA/SinglePopNPDA.cpp

alib2data/src/automaton/PDA/VisiblyPushdownDPDA.cpp

alib2data/src/automaton/PDA/VisiblyPushdownNPDA.cpp

alib2data/src/automaton/TA/DFTA.cpp