add resnet50 example (#3266)
add resnet50 example (#3266)

* add resnet50 example

* fix PEP8 problems

* fix PEP8 problem....again...

This script get 10 points in PEP8 tests on my computer but.....

* add resnet 50

* fix problem caused by interrupted git push

* fix PEP8 problem..again!

* update weights links and remove load_weights

* fix pep8!

* remove skimage dependency, rename the file

* fix pep8...

* update

* support tf dim_ordering

* fix PEP8 problem

keras-team/keras,relh/keras,keras-team/keras,kemaswill/keras,kuza55/keras,DeepGnosis/keras,dolaameng/keras,nebw/keras