simplify constructors of tree structures

alib2data/src/tree/common/TreeAuxiliary.cpp

alib2data/src/tree/common/TreeAuxiliary.h

alib2data/src/tree/ranked/PrefixRankedBarPattern.cpp

alib2data/src/tree/ranked/PrefixRankedBarPattern.h

alib2data/src/tree/ranked/PrefixRankedBarTree.cpp

alib2data/src/tree/ranked/PrefixRankedBarTree.h

alib2data/src/tree/ranked/PrefixRankedPattern.cpp

alib2data/src/tree/ranked/PrefixRankedPattern.h

alib2data/src/tree/ranked/PrefixRankedTree.cpp

alib2data/src/tree/ranked/PrefixRankedTree.h

alib2data/src/tree/ranked/RankedNode.cpp

alib2data/src/tree/ranked/RankedNode.h

alib2data/src/tree/ranked/RankedNonlinearPattern.cpp

alib2data/src/tree/ranked/RankedNonlinearPattern.h

alib2data/src/tree/ranked/RankedPattern.cpp

alib2data/src/tree/ranked/RankedPattern.h

alib2data/src/tree/ranked/RankedTree.cpp

alib2data/src/tree/ranked/RankedTree.h

alib2data/src/tree/unranked/UnrankedNode.cpp

alib2data/src/tree/unranked/UnrankedNode.h