* Simplify Evaluator::create logic. Always use ClassRegister to
  create Evaluator.

* It seems some other change breaks the async load. It will cause data
  error in GPU mode.

Change-Id: Ie09fd666ca208994f22e9f83af6072f4d5e6aa1a

* CHECK_XX in glog need the left and right values are both signed or
  unsigned integer. So we could use integer literal syntax in C/C++
  to make literal unsigned or signed. Add suffix 'UL' means unsigned
  long.

I am getting following error without this commit when doing docker build.

  File "<string>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/setuptools/__init__.py", line 12, in <module>
    import setuptools.version
  File "/usr/local/lib/python2.7/dist-packages/setuptools/version.py", line 1, in <module>
    import pkg_resources
  File "/usr/local/lib/python2.7/dist-packages/pkg_resources/__init__.py", line 70, in <module>
    import packaging.version
ImportError: No module named packaging.version

No idea why this change fix the problem, but it does fix.