Remove old material

baseline/baseline.ipynb

baseline/en_ewt-ud-dev.conllu

baseline/en_ewt-ud-train-projectivized.conllu

baseline/projectivize.py

challenge/challenge.ipynb

challenge/dev.txt

challenge/test-notags.txt

challenge/train.txt

labs/l1-advanced/nlp-l1-advanced.pdf

labs/l1-advanced/wiki.test.tokens

labs/l1-advanced/wiki.train.tokens

labs/l1-advanced/wiki.valid.tokens

labs/l1-basic/nlp-l1-basic.ipynb

labs/l1-basic/wiki.train.tokens

labs/l1-basic/wiki.valid.tokens

labs/l2-advanced/cbow-starter.py

labs/l2-advanced/nlp-l2-advanced.pdf

labs/l2-advanced/sst-5-dev.txt

labs/l2-advanced/sst-5-train.txt

labs/l2-basic/nlp-l2-basic.ipynb