support viewfs

`[16:06:54] include/dmlc/././logging.h:208: [16:06:54] src/io.cc:57: unknown filesystem protocol viewfs://
terminate called after throwing an instance of 'dmlc::Error'
what(): [16:06:54] src/io.cc:57: unknown filesystem protocol viewfs://
Exception in thread Thread-1:
Traceback (most recent call last):
File "/usr/lib64/python2.7/threading.py", line 811, in __bootstrap_inner
self.run()
File "/usr/lib64/python2.7/threading.py", line 764, in run
self.__target(*self.__args, **self.__kwargs)
File "/data/home/GPkuaibaofst/model_train/train/bin/tracker/dmlc_tracker/tracker.py", line 363, in
target=(lambda: subprocess.check_call(self.cmd, env=env, shell=True)), args=())
File "/usr/lib64/python2.7/subprocess.py", line 542, in check_call
raise CalledProcessError(retcode, cmd)`
I am wondering if difacto will support viewfs ?