Some preliminary cleanup
Creating a label-count-map function to replace the old extract-data-for-barchart, splits multiple-select data appropriately
Multiple select charts, towards #452, needs QA.
Adding some tests for lable-count-pairs and select one data
Testing select one bars more explicitly
Some renaming + added tests for select one and select multiple charts
Added some tests about nil data to the charts
Little cleanup, one more test!
Merge pull request #847 from onaio/452_multiple_select_chart

452 multiple select chart