/// These sanitization techniques may allocate more memory for the result than was allocated before
/// for source string
/// These techniques are made to be really fast but the result may not be as pretty as you
/// expected it to be with the allocating techniques.
/// # Examples
/// ```
/// use xssan::prelude::*;
/// // string with html
/// let a = "<h1>Title</h1><p> paragraph.</p>";
/// // this function removes all html tags
/// assert_eq!("Title paragraph.", remove_html_tags(a.clone()));
/// // this function will convert the html tags to be displayed as html tags.
/// // But it will not be executed as html.
/// assert_eq!("<h1&rt;Title</h1&rt;<p&rt; paragraph.</p&rt;", sanitize_string(a));
///
/// ```