chore(package.json): use traceur#0.0.33 until dependencies can cope with 0.0.66

There are a number of breaking changes in more modern traceur versions, such as:

- sourceMap option renamed to sourceMaps
- filename option removed, it is now a parameter of the compile function
- result.errors may not be defined / not an array if no errors occur
- for some reason, either tests are not being preprocessed, or else karma-traceur-preprocessor
  freaks out when it sees the "import" keyword in tests. (I am not sure yet if this is a traceur
  issue, or a bug in pipe or something).

Rather than wait for fixes in each of the dependency projects affected by this break, instead
we will just use a LKGR of traceur, which seems to work well enough. Fixes in the dependency
tools should get this working, but perhaps not until a traceur#v0.1.0 ships.

Closes #70
Closes #71

Author: caitp

package.json

@@ -12,7 +12,7 @@
     "url": "https://github.com/angular/di.js/issues"
   },
   "dependencies": {
-    "traceur": "~0.0.33",
+    "traceur": "0.0.33",
     "es6-shim": "~0.11.0"
   },
   "devDependencies": {