Set the `non_uppercase_statics` lint to warn by default
Update the `unused` lint group to include more lints
Improve the `non_snake_case` lint to give better suggestions
Correct error message for invalid `ref`/`mut` bindings

Closes #15914.
Report trait/impl sig inconsistency before method/body inconsistency

Closes #15657.
Change rustc pretty-printing to print [T, ..n] instead of [T, .. n]
Move the lint for the stability lints to the method name only

Closes #17337.