Do not sort functions, types and constants in generated docs

The rationale is to let them in the order they are defined, so that
  library authors have some freedom in how they present information. On
  top of that, we'll also now parse specifi comments as section headers
  that will be inserted in the sidebar when present.

crates/aiken-project/src/docs.rs

@@ -159,7 +159,6 @@ fn generate_module(
         .definitions
         .iter()
         .flat_map(DocFunction::from_definition)
-        .sorted()
         .collect();
     functions
         .iter()
@@ -171,7 +170,6 @@ fn generate_module(
         .definitions
         .iter()
         .flat_map(DocType::from_definition)
-        .sorted()
         .collect();
     types
         .iter()
@@ -183,7 +181,6 @@ fn generate_module(
         .definitions
         .iter()
         .flat_map(DocConstant::from_definition)
-        .sorted()
         .collect();
     constants
         .iter()