Fixes an error failing to parse if there is a newline after the attri…

…bute.

src/element_parser.rs

@@ -47,7 +47,7 @@ pub fn parse<'a>(token: &'a tokenizer::Token) -> Option<Element<'a>> {
                                 }
                             },
                             State::Name(start) => match current_char {
-                                ' ' => {
+                                ' ' | '\n' => {
                                     pairs.push((&target[start..pos], None));
                                     state = State::NameEnd;
                                 }