code refactoring

maca_lemmatizer/src/context.c

maca_lemmatizer/src/context.h

maca_trans_parser/src/beam.c

maca_trans_parser/src/context.c

maca_trans_parser/src/context.h

maca_trans_parser/src/depset.c

maca_trans_parser/src/feat_fct.c

maca_trans_parser/src/feat_vec.h

maca_trans_parser/src/queue.c

maca_trans_parser/src/queue.h

maca_trans_parser/src/stack.c

maca_trans_parser/src/stack.h

maca_trans_parser/src/transform_treebank.c