update error filtering so it checks for severity instead of just type

src/compiler.js

@@ -36,7 +36,7 @@ function compileFileOrFiles (filename, isDirectory, cb) {
       compiler.compile(sources, filepath)
     }
   ], function (err, result) {
-    let errors = (result.errors || []).filter((e) => e.type === 'Error')
+    let errors = (result.errors || []).filter((e) => e.type === 'Error' || e.severity === 'error')
     if (errors.length > 0) {
       console.dir(errors)
       return cb(new Error('errors compiling'))