macro_rules! doesn't work

[jethrogb]

If you register the macro_rules! macro like so:

let mut reg = syntex::Registry::new();
reg.add_ident_macro("macro_rules",syntex_syntax::ext::tt::macro_rules::MacroRulesExpander);

you'll get this error:

error: internal compiler error: add_macro is not supported yet
 --> src/main.rs.in:1:1
  |
1 | macro_rules! ...
  | ^

Which seems to be related to https://github.com/serde-rs/syntex/blob/389b280/syntex/src/resolver.rs#L39-L43