Macro rumtk_web_render_markdown 

macro_rules! rumtk_web_render_markdown {
    ( $md:expr ) => { ... };
}

If using raw strings, do not leave an extra line. The first input must have characters, or you will get

 blocks regardless of what you do.

Example
use rumtk_web::rumtk_web_render_markdown;

let md = r###"
**Hello World**
"###;
let expected_html = "<p><strong>Hello World</strong></p>\n";

let result = rumtk_web_render_markdown!(md);

assert_eq!(result, expected_html, "The rendered markdown does not match the expected HTML!");