MREF control with AND/OR dropdown front of de select2 and '+' and '-'
after
use "mini" class to create smaller buttons
no AND/OR button for range/data/int, add a "or" label
use bootstraps ".add-on" to "glue" controls together
fix style
Merge branch 'master' of github.com:molgenis/molgenis into feature/simplified_filter_UX_2649
Merge branch 'master' of github.com:molgenis/molgenis into feature/simplified_filter_UX_2649
Merge pull request #1688 from jjettenn/feature/simplified_filter_UX_2649

Feature/simplified filter ux 2649