Change test runner to use a module loader

This changes the test runner to use the module loader. The main motivation for this is that I'm planning to remove module definitions (they are no longer in the proposal). To continue to have test coverage we therefore need to use external module files.

This fixes a few more issues that were needed to be fixed to get this working:

- `export * from 'name'` was not using the temp variable in the getter.
- The `CloneTransformer` was not up to date. The reason was that these tests were not run by default before. Now we run these at all times.
- Added support for a translate hook to the loader. This was needed to allow us to extract the options before we do parsing.

Review URL: https://github.com/google/traceur-compiler/pull/377

Closes #377.
Resynchronize bin/traceur.js

This is just the result of
  make clean force test
to synchronize the bin and source in the repo.
Merge pull request #388 from johnjbarton/resync

Resynchronize bin/traceur.js

This is just the result of
make clean force test
to synchronize the bin and source in the repo.
Fixes #385, missing location start for ImportSpecifierSet
Merge pull request #386 from johnjbarton/startModuleSpecifierSet

Fixes #385, missing location start for ImportSpecifierSet

For case where import statement does not use curly braces.
Added test ImportSpecifierSetSourceMap, sourcemap needed to trigger location read.