Coh customization

[samjaros-stanford]

Add cohort customization functionality

• Resolves #6 - Timing can be customized by cohort. Timing responds to changes in cohort. Uses main timings as default. Rearrange timings if timings are rearranged in cohort tab.

• Resolves #7 - Implemented sortable to allow for interventions to be reordered or removed by cohort

• Fixes #10 - Smarter drawing of intervention timing

[samjaros-stanford]

• Removes old development code and dependencies
• (Attempts to) standardize naming/usage