Outlives vs Trait Goal Syntax Collision

[compiler-errors]

Both use : in Rust, but the colon is always parsed as outlives in formality.

This was confusing when @jackh726 wrote his projection PR, since it looked like trait goals were failing when they were erroneously parsed as outlives.

Syntax should be changed or some type of validation could perhaps be written to make sure we never try to outlive a trait name on the RHS.