Beta API does not work with authentication

Issuing any Beta API request that requires authentication results in HTTP 500 response. The logs show that this is caused by a Shiro UnavailableSecurityManagerException, which is thrown when ShiroAuthenticatingThriftInterceptor tries to acquire the current Shiro Subject (see attachments for full stack trace).

The reason for this seems to be twofold:

• The Jersey GuiceContainer serving the API is installed as a filter, and during request processing that filter is activated before any of the Shiro filters are. Therefore Shiro has not yet been initialized when ShiroAuthenticatingThriftInterceptor is run.

• There is no ShiroWebModule.guiceFilterModule installed for /apibeta/*, so the authentication filters would not be executed even if the filters were installed in a proper order.

The attached patch for Aurora 0.17.0 seems to fix the filter ordering issue by installing the GuiceContainer as a servlet. It also makes sure that UnauthenicatedExceptions thrown from auth interceptors are propagated properly.