Made "version" a required argument to Study (so "save" of a study bumps the version number correctly)
move expression threshold to be on the raw data, not hte logged data
Merge branch 'release/0.1.0' of github.com:YeoLab/flotilla into release/0.1.0

* 'release/0.1.0' of github.com:YeoLab/flotilla:
  Make sure set1 is only hex, not rgb colors
  Convert randomly assigned phenotype colors to hex colors from rgb
  Fix violinplots when there are not outlier cells, and