Fix oefeningen misspelling
Merge branch 'fix/30'
Merge branch 'master' of https://github.com/PerceptumNL/KhanLatest
Merge branch 'master' of https://github.com/PerceptumNL/KhanLatest
Merge branch 'master' of https://github.com/PerceptumNL/KhanLatest
Fix videos readable_id which were showing as undefined