Merge pull request #130 from erwinwinder/master

Added dataset indexer plugin
add catagorical feature values
Merge branch 'master' of https://github.com/molgenis/molgenis
bug fix: close stream, bug fix: transaction per observationset instead of per daa
Small enhancements
Merge pull request #132 from dennishendriksen/master

Add categorical feature values in data explorer + importer fixes
Merge branch 'master' of https://github.com/molgenis/molgenis