Created by: walloollaw

improvements: 1, fix bug in batch_norm layer when the 'eps' value changed from default value 1e-5 2, fix bug in pool layer when we need 'ceil_mode'(change default to this mode) 3, add more tools to compare the results generated by converted fluid model with caffe model 4, upgrade the fluid interfaces used by caffe2fluid to the latest version

now, all models(listed in README.md) has been checked for precision，the precision difference is under 1e-5