[NT-1315] Native Project Cards Design Tweaks

[ifbarrera]

📲 What

A couple design tweaks and small bug fixes for the Native Project Cards experiment.

🤔 Why

Final cleanup in preparation to release this experiment.

🛠 How

• fixes a bug where large numbers in the backers count label were not being properly formatted
• fixes a bug where the "Save" button wasn't working properly because not all the outputs were hooked up to the view model
• adds a shadow to the project status tag and the "Save" button to improve contrast against light backgrounds
• decreases the top and bottom margins on the project status tag view

👀 See

Trello, screenshots, external resources?

After 🦋	Before 🐛

✅ Acceptance criteria

Whitelist your device into the native_project_cards experiment.

• Run the app. Find a project with a large number of backers. The backer count should appear larger than the backers text, and should be bolded
• Saving and un-saving projects in discovery should work as expected, and should generate feedback when run on a device
• The project status tag view and the save button should have a very subtle shadow

[justinswart]

lgtm!