PAC Snapshot: build snapshot front-end

[rfultz]

Summary

What we're after
As a potential contributor to PACs and party committees, I want to better understand how my contributions may be used, so that I can make more informed decisions.

Related issues

See epic: fecgov/fec-epics#202

Completion criteria

• PAC snapshot matches mockup (to be updated at the end of 15.2)
• Include automated tests

Tech steps or considerations

• Use a feature flag
• Populate top line numbers
• Percentage descriptions
• Committee raising and spending descriptions
• Committee type descriptions and glossary terms
• Anything else in the mockup not included here