Don't overwrite sys.meta_path in nltk.compat
Merge pull request #524 from pickl-it/meta_path

Don't overwrite sys.meta_path in nltk.compat
Fixed variable scoping bug.
replace ngram functions with their iterator counterparts, cf https://github.com/nltk/nltk/issues/527
Merge pull request #528 from jskda/master

Replace ngram functions with their iterator counterparts, cf https://github.com/nltk/nltk/issues/527
updates to NLTK URL and email addresses
Fixed bug in 'ne_chunked' demo. Some renaming of functions and tidying up.
Temporary(?) fix for zip files
Merge branch 'master' of https://github.com/nltk/nltk
return lists instead of zips for small lists, to save complicating the book