Added a tidy param to element.to_string
Added with_doctype option to html_tidy
Added extract method to HtmlElement
Whitespace fix
Made extract method deal with tail
Added index to extract
Made extract handle ordering
Made replace handle text properly
Made add method handle empty path
Used isinstance for Comment test
Made Comments count as empty tags
Refactored empty test in html_tidy
Fixed creation of disabled form_fields
Upped version to 0.2.12
Refactored Transform to be immutable
Fixed more disabled form_fields
Fixed element.add
Improved element.replace with text
Small refactor to element.replace
Merge branch 'feature/bug_fixes' into develop