Replace variant resource SolveBio queries with JS dashboard code

SolveBio API queries are proxied through a Django view in Varify (`/api/solvebio/`).
The variant details modal loads a local iframe (`/api/solvebio/dashboards/variant-detail`) which is an AngularJS app that queries the local SolveBio API proxy for data, and presents the results in ClinVar and Medline widgets. 
Queries are initiated when the variant detail modal loads. Also, the SolveBio query from the variant API resource was removed (speeds up the results page).

Questions:
* What is the recommended way to make loading `solvebio.js` optional?
* Are you ok with an external S3 dependency, or would you rather bundle our JS code within the app?

Signed-off-by: David Caplan <dcaplan@gmail.com>