allow rustfmt to reorder imports

This wasn't a right decision in the first place, the feature flag was
broken in the last rustfmt release, and syntax highlighting of imports
is more important anyway

crates/ra_ide_api/src/assists.rs

@@ -1,6 +1,6 @@
-use ra_db::{FileRange, FilePosition};
+use ra_db::{FilePosition, FileRange};
 
-use crate::{SourceFileEdit, SourceChange, db::RootDatabase};
+use crate::{db::RootDatabase, SourceChange, SourceFileEdit};
 
 pub use ra_assists::AssistId;