“73f4601da8d0fc376240db36bf95fc84880906c7”上不存在“paddle/phi/api/lib/api_registry.h”
* Fix bug in MergeModel.cpp. * Add a c-api inferface to initilize the thread environment of Paddle and add a GPU example. * Add some note for paddle_init_thread and move the inplementation of paddle_error_string into a .cpp file. * Add some comments.