Build MDC-based tabs

[mmalerba]

Tasks

• Scaffold empty classes, assets, demo, build config, etc.
• Stub existing component API
• Hook up MDC foundation and adapter
• Add remaining features on top of MDC implementation
• Test dark theme
• Test RTL
• Test with screen-readers
• Copy existing unit tests and ensure they all pass
• Copy existing e2e tests and ensure they all pass (if any)
• Verify SSR support in universal-app/
• Verify no size regression
• Create test harness
• Create schematics for migration
• Create user documentation

Additional notes

Breaking changes

Known issues & visual differences