* add api check in fc test=develop
* enforce shape error info of sum op test=develop
* fix spelling test=develop
* print x_dims info test=develop
* enhance shape error info test=develop
* Refine the codes related to fc op.
* Add GPU implementation for fc functor.
* Apply fc_fuse_pass in GPU inference.
test=develop
* Change the cmake for fc op.
* Change PADDLE_ENFORCE to PADDLE_ENFORCE_EQ.
* Add an attribute to set the activation type in fc_op.
* Enhance the unittest of fc_op.
test=develop
* Remove the declaration of FCOpGrad back to the header file.
test=develop
* Set default value for newly added arguments in test_fc_op.
test=develop
Aurelius84
Yiqun Liu
tensor-tang
mozga-intel