fixed typo and added doc-comment

Author: funkill

src/renderer/html_handlebars/hbs_wrapper.rs

@@ -81,7 +81,7 @@ fn build_header_links(html: &str) -> String {
         .into_owned()
 }
 
-/// Insert a sinle link into a header, making sure each link gets its own
+/// Insert a single link into a header, making sure each link gets its own
 /// unique ID by appending an auto-incremented number (if necessary).
 fn insert_link_into_header(
     level: usize,
@@ -170,6 +170,7 @@ fn add_playpen_pre(html: &str, playpen_config: &Playpen) -> String {
         .into_owned()
 }
 
+/// Split source code to module-level attributes (from head of text) and rest text
 fn partition_source(s: &str) -> (String, String) {
     let mut after_header = false;
     let mut before = String::new();