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Merge pull request #106 from Oona/master

Lecture 8 link to 'Issues for adding automated testing'.
Merge pull request #107 from tariel/master

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@Oona found alanshaw/david-www
A word of clarification
Lecture 9, task 2.
Merge pull request #108 from HeikkiAlanen/master

Lecture 9, task 2.