Make fails

[kumavis]

$ make browser
iced -c -I browserify lib/interpreter.coffee
lib/interpreter.coffee:243:11: error: await'ed statements can't act as expressions
          for arg in node.arguments
          ^^^^^^^^^^^^^^^^^^^^^^^^^
make: *** [lib/interpreter.js] Error 1

https://github.com/int3/metajs/blob/master/lib/interpreter.coffee#L243-L245

[omphalos]

Seems there were breaking changes in IcedCoffeeScript. Specifying the version (I've been using 1.4.0-c) seems to work. I updated the README and package.json with this info.