Function mod_utilities::escape_str_into

pub fn escape_str_into(source: &str, dest: &mut String)

Unescape special character sequences into their serialization-safe equivalent

For example \n becomes two characters, \ followed by n

Utf escapes to be in the format \uXXXX where X are hex digits

This version copies onto the end of an existing String, use escape_str to use a new String