Add 'Idiomatic Rust' to the course structure section

Author: LukeMathWalker

mdbook-course/src/replacements.rs

@@ -48,7 +48,8 @@ pub fn replace(
                 ["course", "outline"] if course.is_some() => {
                     course.unwrap().schedule()
                 }
-                ["course", "outline", course_name] => {
+                ["course", "outline", course_name @ ..] => {
+                    let course_name = course_name.join(" ");
                     let Some(course) = courses.find_course(course_name) else {
                         return format!("not found - {}", captures[0].to_string());
                     };

src/running-the-course/course-structure.md

@@ -72,6 +72,16 @@ cargo run
 
 {{%course outline Concurrency}}
 
+### Idiomatic Rust
+
+The [Idiomatic Rust](../idiomatic/welcome.md) deep dive is a 2-day class on Rust
+idioms and patterns.
+
+You should be familiar with the material in
+[Rust Fundamentals](../welcome-day-1.md) before starting this course.
+
+{{%course outline Idiomatic Rust}}
+
 ## Format
 
 The course is meant to be very interactive and we recommend letting the