Replaced python 2.x xrange to python 3.x range
Merge pull request #673 from helmanofer/ofer_dev

Replaced python 2.x xrange to python 3.x range
Merge pull request #672 from jskda/pull_request.tests

Fixes to unit tests
whitespace normalisation
re-applied changes from https://github.com/nltk/nltk/commit/8dc5f5b5fda42ceff08ac7d3d47d1f795b30dfc3, cf https://github.com/nltk/nltk/issues/670
re-applied changes from https://github.com/nltk/nltk/commit/160a85d4551b3f629e725d1ee4a9f99666b75b45, cf https://github.com/nltk/nltk/issues/670
re-applied changes from https://github.com/jskda/nltk/commit/06d75ceaec1c561d5d5548b597db6e6bb26eb0a3, cf https://github.com/nltk/nltk/issues/670
re-applied changes from https://github.com/heatherleaf/nltk/commit/c65dffdf4bf10a81aa07e508175f7818a12f5183, cf https://github.com/nltk/nltk/issues/670
version 3.0a4
removed the polymorphism from the multilingual wordnet methods which would return an object or a collection of objects, depending on whether they are called with a single language or multiple languages, cf https://github.com/nltk/nltk/issues/505
updates for first beta release
fixed & updated collocations unit tests