Testing the network training procedure visualize tool -- tensorboard on a simple CNN model on MNIST and delete some unuse log files.

Changing some logical code to adapt tensorboard and keras's callback function.

remove wrong png files.

remove useless log files.

gitignore update: ignore some log files

end up a simplt vgg16 network model on CIFAR10 with about 80% accuracy.

initialize with some old work

Initial commit