docs: cleanup the explanation paragraphs at the start of each exercise.

exercises/options/options1.rs

@@ -1,5 +1,7 @@
 // options1.rs
-// Execute `rustlings hint options1` or use the `hint` watch subcommand for a hint.
+//
+// Execute `rustlings hint options1` or use the `hint` watch subcommand for a
+// hint.
 
 // I AM NOT DONE
 
@@ -7,8 +9,9 @@
 // If it's before 10PM, there's 5 pieces left. At 10PM, someone eats them
 // all, so there'll be no more left :(
 fn maybe_icecream(time_of_day: u16) -> Option<u16> {
-    // We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a value of 0
-    // The Option output should gracefully handle cases where time_of_day > 23.
+    // We use the 24-hour system here, so 10PM is a value of 22 and 12AM is a
+    // value of 0 The Option output should gracefully handle cases where
+    // time_of_day > 23.
     // TODO: Complete the function body - remember to return an Option!
     ???
 }
@@ -28,7 +31,8 @@ mod tests {
 
     #[test]
     fn raw_value() {
-        // TODO: Fix this test. How do you get at the value contained in the Option?
+        // TODO: Fix this test. How do you get at the value contained in the
+        // Option?
         let icecreams = maybe_icecream(12);
         assert_eq!(icecreams, 5);
     }

exercises/options/options2.rs

@@ -1,5 +1,7 @@
 // options2.rs
-// Execute `rustlings hint options2` or use the `hint` watch subcommand for a hint.
+//
+// Execute `rustlings hint options2` or use the `hint` watch subcommand for a
+// hint.
 
 // I AM NOT DONE
 
@@ -27,8 +29,9 @@ mod tests {
 
         let mut cursor = range;
 
-        // TODO: make this a while let statement - remember that vector.pop also adds another layer of Option<T>
-        // You can stack `Option<T>`s into while let and if let
+        // TODO: make this a while let statement - remember that vector.pop also
+        // adds another layer of Option<T>. You can stack `Option<T>`s into
+        // while let and if let.
         integer = optional_integers.pop() {
             assert_eq!(integer, cursor);
             cursor -= 1;

exercises/options/options3.rs

@@ -1,5 +1,7 @@
 // options3.rs
-// Execute `rustlings hint options3` or use the `hint` watch subcommand for a hint.
+//
+// Execute `rustlings hint options3` or use the `hint` watch subcommand for a
+// hint.
 
 // I AM NOT DONE