added new index for reproduced paper notebook [Groblacher et. al., Nature 460, 724 (2009).]
Merge branch 'master' of https://github.com/reproduced-papers/reproduced-papers.github.io
Merge pull request #2 from eunjongkim/master

added new index for reproduced paper notebook [Groblacher et. al., Nature 460, 724 (2009).]