Some functions which applies to scoped tags in general moved from TaskTag to Task model.
Also, some stylish and whitespace changes and docstrings added.
/**
* @param {Page[]} pages
* @param {number} [id] Specifies the id, if applicable.
* @param {String} [title = This is untitled.] Specifies the title.
*/
function Document(pages, id, title){
}