* Fix for embedding gradient calculation
- Passes vectors instead of scalars to slice
- converts the numRows to a scalar
- add `toScalar` utility function
- minor change to test case so that it actually works
* added lib for testing helper functions
* add flatSlice function
* Use native oneHot op in the example code. It didn't exist when this was originally written.
* Misc cleanup in MNIST example
- Use unspecified dimension for batch size in model. This simplifies the
code for the test set.
- Move error rate calculation into model.
Greg Steuck
Noon van der Silk
Greg Steuck
fkm3