Proper import of errors from oauth_provider

[atlefren]

Fix the fact that InvalidConsumerError and InvalidTokenError wasn't imported correctly from oauth_provider. ref https://groups.google.com/forum/?fromgroups=#!topic/django-rest-framework/V5kVUQchSec

[tomchristie]

There's one other place where oauth_provider_store is used. Is it possible to also change that one and then drop the oauth_provider_store import completely?

[atlefren]

as far as i can see, oauth_provider_store is now used three places in authenticate.py:

• get_consumer
• get_access_token
• check_nonce

I guess it could be possible to import just oauth_provider, and somehow call
oauth_provider.store.store.get_consumer()

etc..

though, I'm not quite sure of this, and I am a but relucatant to mess around too much with code I really don't know that well