Merge pull request #5 from kmkr/label-programming-exercise

Label programming exercise in task 6

Added @kmkr to contributors

Merge pull request #3 from kmkr/remove-unused-variable

Merge pull request #4 from kmkr/add-python-tk-as-requirement

Merge pull request #2 from kmkr/master

Add python-tk as a dependency

Use the function supplied as argument

Remove unused variable

Added topics to weekly exercises in README

Fixed broken links.

Updated group lecture notes for 2017

Moved group lecture notes into subfolder

Prepared for 2017, finished all exercises/assignments

Added esb1 as contributor and updated description