Integrate CRF in DeepText + New caffe2 operator for viterbi decode
Integrate CRF in DeepText + New caffe2 operator for viterbi decode

Summary: Inegration of the CRF Layer in DeepText wordmodels + Implementing the viterbi decode operator in C++ instead of python so that the CRF models can be deployed in production.

Differential Revision: D4912196

fbshipit-source-id: 64f499a1bd47e811e7a96dde839904dcd05cacb3

davinwang/caffe2,sf-wind/caffe2,davinwang/caffe2,pietern/caffe2,sf-wind/caffe2,bwasti/caffe2,pietern/caffe2,sf-wind/caffe2,Yangqing/caffe2,bwasti/caffe2,pietern/caffe2,sf-wind/caffe2,bwasti/caffe2,Yangqing/caffe2,xzturn/caffe2,bwasti/caffe2,Yangqing/caffe2,davinwang/caffe2,pietern/caffe2,xzturn/caffe2,xzturn/caffe2,caffe2/caffe2,sf-wind/caffe2,Yangqing/caffe2,Yangqing/caffe2,davinwang/caffe2,xzturn/caffe2,pietern/caffe2,xzturn/caffe2,bwasti/caffe2,davinwang/caffe2