Merge branch 'dev_handle_long_seq' into 'master'

CHANGELOG.md

core/poldeepner.py

data/cen_n82/train.txt

data/cen_n82/valid.txt

evaluate_tsv.py

main.py

poldeepner2/utils/data_utils.py

poldeepner2/utils/sequence_labeling.py

poldeepner2/utils/sequences.py

poldeepner2/utils/train_utils.py

tests/resources/POLEVAL-NER_GOLD-sm.json

tests/resources/plaintext.json

tests/resources/poleval_0337_annotations.txt

tests/resources/poleval_0337_iob.tsv

tests/resources/poleval_0337_text.txt

tests/resources/poleval_to_iob.iob

tests/resources/poleval_to_iob.json

tests/resources/poleval_to_iob_target.iob

tests/resources/tsv_test.tsv

tests/unit/utils/test_read_tsv.py