[misc] Upgrade logback to 1.1.6
[misc] Upgrade logback to 1.1.6

alexhenrie/phenotips,teyden/phenotips,tmarathe/phenotips,teyden/phenotips,phenotips/phenotips,tmarathe/phenotips,phenotips/phenotips,teyden/phenotips,alexhenrie/phenotips,phenotips/phenotips,teyden/phenotips,phenotips/phenotips,alexhenrie/phenotips,teyden/phenotips,phenotips/phenotips,tmarathe/phenotips