Add numpy.linalg as a mock module for API docs.
Add numpy.linalg as a mock module for API docs.

\cc @Godrek

Alexx-G/openface,Alexx-G/openface,cmusatyalab/openface,nmabhi/Webface,xinfang/face-recognize,nmabhi/Webface,xinfang/face-recognize,Alexx-G/openface,nmabhi/Webface,Alexx-G/openface,francisleunggie/openface,xinfang/face-recognize,francisleunggie/openface,cmusatyalab/openface,francisleunggie/openface,cmusatyalab/openface,nmabhi/Webface