Merge pull request #53 from ascott1/dev

Amortized calculations
add respond.js polyfill
pin Capital Framework dependencies
add aria roles
make downpayment placeholder 10%
calculate the median of the total results
use npm amortize module
remove local amortize files
Merge pull request #55 from ascott1/dev

respond.js, pin dependencies, and add aria roles
Fix ARM values
Improve method documentation
Remove downpayment from API request
Merge upstream
Merge pull request #56 from contolini/dev

ARM and API improvements
calculate and display a plain language comparison summary
Merge pull request #57 from ascott1/plainLangSum

Plain language summary
Update ARM API parameter values
Merge branch 'dev' of github.com:cfpb/owning-a-home into dev
Select largest rate in second comparison dropdown
Merge pull request #58 from contolini/dev

ARM API update and comparison section improvement