New Features
* **99% test coverage**
* all tests rewritten from scratch
* removed all framework-specific duplication
* added nice helper functions
* truely lazy imports of the different frameworks
* added *magic* framework wrappers that automatically apply `ep.astensor` and preform lazy imports
* `ep.torch`
* `ep.tensorflow`
* `ep.numpy`
* `ep.jax`
* added `pow()`
* added `log_softmax()`
* added `kl_div_with_logits()`
* **lots of bugfixes and improvements**