Did you know? The .gitignore inside skeleton/ was actually affecting
twitter_ebooks's repo. This fixes that by moving it for twitter_ebooks,
and moving it back when people make their repositories!
corpus/* matches all files in the first level directory inside corpus,
so it would match corpus/lala.txt but not corpus/secret/lala.txt.
corpus/ matches the directory corpus itself, meaning that corpus/ and
everything inside of it shouldn't be uploaded.
corpus/** matches everything inside corpus, including contents of
subdirectories, while still allowing corpus/ itself to be uploaded. This
solves the initial problem I posed (with corpus/secret/lala.txt), but it
just feels tidier to just remove the entire folder.
