added assignment4 sparql questionnaire
Merge remote-tracking branch 'upstream/master'
Merge remote-tracking branch 'upstream/master'
added work
corrected link requirements
Merge remote-tracking branch 'upstream/master'
Merge pull request #160 from n-lopez/master

The analysis of how the dataset requirements are satisfied is missing.
It is also not clear how the datasets will be linked, taking into account that links have to be performed in terms of entities, not of values (e.g., coordinates).