Hotfix for gcloud-0.18.3.
Hotfix for gcloud-0.18.3.

+ Blog.new_blob() => Blog.blob()
+ Add ValueError handling for the error below:

```
  File "/home/m157q/github/Tagtoo/dashboard/lib/django-gcloud-storage/django_gcs/storage.py", line 65, in _save
    gc_file.upload_from_file(content.file)
  File "/home/m157q/.virtualenvs/dashboard/lib/python2.7/site-packages/gcloud/storage/blob.py", line 518, in upload_from_file
    raise ValueError('total bytes could not be determined. Please '
ValueError: total bytes could not be determined. Please pass an explicit size, or supply a chunk size for a streaming transfer.
```

littleq0903/django-gcloud-storage