added icons to rationale view
use FA variables, embed &:before blocks within classes
fix coverage measure data critieria calculation
the measure data criteria calculation for coverage was using all data criteria from the measure.  This is not the correct approch.  Instead we want to only use the referenced data criteria for a population
population criteria should come off of the population rather than off of the measure
Cache patient results by CID so that clones have different results
Small code cleanup in patient materialization
Remove the obsolete matrix view (no longer worked with deferred calculation)
Merge pull request #42 from projecttacoma/rationale_icons

added icons to rationale view