Ability to quality all imports for a given import

[jun-sheaf]

When working with a large codebase with many different types, types often need to be aliased or partially/fully qualified to distinguish it from a different type of the same name.

For example,

use geo::Point;
use a::b::generated::Point;

let x: Point; // Eh? Which one?

User flows

This issue proposes the following flow:

Replace use with qualified path

For qualifying a useed type, one would:

1. Right-click a used type.
2. Click "Replace use with qualified path".
3. Observe that all imports are fully qualified.