Add UpSampling layers

[mkaze]

Currently, the support for UpSampling layers is missing and it would be great if we could add support for these layers as well. The desired PR addressing this issue should include:

• Implementation of layers classes named as UpSampling1D, UpSampling2D and UpSampling3D.
• Common hierarchy of all UpSampling layers with abstract class with the common functionality
• Documentation of layer and all non-private methods
• JUnit tests in api module
• Support for export of layers to JSON (see ModelSaver.kt)
• Support for import of layers from JSON (see ModelLoader.kt)

Also, if needed, you can take a look at Keras documentation for these layers: UpSampling1D, UpSamplling2D and UpSampling3D.

NOTE: for the moment, there is no need to add support for "data format" (i.e. channels last vs. channels first) in your PR; you can simply assume the channels are always in the last dimension.

[mkaze]

I'll take this one.

[zaleslaw]

It's a very interesting bunch of layers, @mkaze good luck with that, it includes a lot of functionality in the Keras, we should try to avoid repeating all of it, ignoring things not related to the current state of the KotlinDL