Update solitude logo + links
Add a verify service ID API (bug 991528)

- Add client endpoint for service prices
- Use service prices to determine whether a service id is valid for use with integrator account
- Add API view, tests
- Documentation
Merge pull request #219 from JaredKerim-Mozilla/991528

Check that a merchant ID is using the Mozilla integrator account (bug 99...
Log info about invalid Boku prices
Merge pull request #222 from muffinresearch/update-solitude-logo

Update solitude logo + links
proxy through the provider (bug 992381)