Octopod

Changed
- Torch is no longer pinned to version 1.2. This allows user to use Octopod with python 3.8.

Fixed
- Support for `torch.optim.lr_scheduler.ReduceLROnPlateau` for `scheduler` argument in `MultiTaskLearner.fit`
- Learner object skips and `ResnetForMultiTaskClassification` `forward` method automatically handles batches of size 1 to avoid `ValueError` with `nn.BatchNorm1d` failing on batches of size 1

Added
- logo now in octopod readme

Added
- Octopod learners can now use multiple loss functions and do multi-label in addition to multi-class tasks
Changed
- loss functions and metrics are specified via a dictionary of tasks and corresponding loss functions

Added
- Warnings to switch to new name

Fixed
- A few paren locations in multi_task_ensemble.py