Tracking issue for current refactoring efforts

[regexident]

Environment:

• Implementing let (or some kind of state for tests) (PR Implement test environments and before/after closures #30)

Before & After

• Implement before_all and after_all (PR Implement test environments and before/after closures #30)
• Real before_each and after_each (PR Implement test environments and before/after closures #30)

Timing & Progress

• Formatter: Progress à la Fuubar
• Timing the tests (WIP)
• Timing the test suite (WIP)

Filtering & Focussing

• Skipped tests and describes (experiment)
• Focused tests and describes (experiment)

Parallel & Async Tests

• Parallel tests (probably via Rayon) (PR Implement test environments and before/after closures #30)
• Async tests

Ergonomics

• Simplify formatter instantiation and runner attachement? (PR Implement test environments and before/after closures #30)
• context::rdescribe should use the Simple formatter (PR Implement test environments and before/after closures #30)
• Get rid of ctx in ctx.it() (experiment)

Integration

• Integration with existing matcher crates
• Integration with rustc's test crate