Added Image.deprecate, ImageApiMockTest completed, removed ImageApiExpec...

...tTest

What do you think of the format of the ImageApiMockTest?

If it looks good, ill start converting others to a similar format. 
I think toString handles the casing, which is why this needed to be changed. @danbroudy can you add a test to make sure this happens? Make GoogleComputeEngineImageToImageTest and pass an input image which is deprecated.