Remove unit test samples

Change-Id: If097ae746e83f794c43c14dca831010c8346f355
Add settings for Excel export, allow uploading an Excel export template in the settings

Change-Id: I393560db2a5d75e287a267ac687cd77db42d049a
Merge branch 'master' of https://github.com/lorenzulrich/GIB.GradingTool