Added function to update the dataset status

* fixes issue #565 and removes future / deprecation warnings

* removes last deprecation warning

* added additional raised error

* changed structure

* Add unit test for list of lists dataset upload

* Fixing xml pattern typo

* Fix pep8 no newline at the end of file

* Remove format from definitions

* Restoring format in dataset

* Fixing a couple of unused imports and fixings bugs with create_dataset call

* Adapting unit tests to changes

* Fixing failing unit tests

* fixing typo

* Enforce pep8 style guide, fix doc tutorial trying to invoke create_dataset with format attribute

* Workaround for pep8 style guide

* fix long time typo

* update pep8 failing statement and bug fix for dataset upload tutorial

* fixed problem with arff file

* Fix pep8 line too long

* Extending the unit test for dataset upload, changing upload tutorial

* Workaround for the dataset upload unit test

* Adding example with weather dataset into the dataset upload tutorial

* Fixing builds failure

* Adding support for sparse datasets, implementing corresponding unit tests

* fix bug

* More unit tests and bug fix

* Fixing bugs

* Fix bug and pep8 errors

* Enforcing pep8 and fixing changing the name of attribute format as it is a built-in

* Implementing change in a better way

* Fixing bugs introduced by changing the format in the constructor

* Another try to tackle the bugs

* Small refactor

* Fixing pep8 error

* Fix python2.7 bug

* making changes in accordance with Guillaume's suggestions

* Adding unit tests, small refactoring

* Enforcing pep8 style

* Following Matthias's suggestions

* Fixing bug introduced by variable name change

* Changing the breast_cancer dataset to diabetes, fixing typo with weather dataset, adding creator of weather dataset

* Further changes

* Adding more changes

* Fixing bug

* Pep8 enforce

* few changes

* Fixing typo in dataset name attributes

…sults are available

Fix #580