Add nn-models to __init__, add PytorchForecastingTransform to __init__

CHANGELOG.md

@@ -24,6 +24,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Regressors does not have enough history bug ([#35](https://github.com/tinkoff-ai/etna-ts/pull/35))
 - make_future(1) and make_future(2) bug
 - Fix working with 'cap' and 'floor' features in Prophet model ([#62](https://github.com/tinkoff-ai/etna-ts/pull/62)))
+- Imports of nn models, PytorchForecastingTransform and Transform ([#80](https://github.com/tinkoff-ai/etna-ts/pull/80)))
 
 ## [1.0.0] - 2021-09-05
 ### Added

etna/models/nn/__init__.py

@@ -0,0 +1,2 @@
+from etna.models.nn.deepar import DeepARModel
+from etna.models.nn.tft import TFTModel

etna/transforms/__init__.py

@@ -1,4 +1,5 @@
 from etna.transforms.add_constant import AddConstTransform
+from etna.transforms.base import Transform
 from etna.transforms.datetime_flags import DateFlagsTransform
 from etna.transforms.datetime_flags import TimeFlagsTransform
 from etna.transforms.detrend import LinearTrendTransform
@@ -10,6 +11,7 @@
 from etna.transforms.outliers import MedianOutliersTransform
 from etna.transforms.power import BoxCoxTransform
 from etna.transforms.power import YeoJohnsonTransform
+from etna.transforms.pytorch_forecasting import PytorchForecastingTransform
 from etna.transforms.scalers import MaxAbsScalerTransform
 from etna.transforms.scalers import MinMaxScalerTransform
 from etna.transforms.scalers import RobustScalerTransform

tests/test_models/nn/test_deepar.py

@@ -7,9 +7,9 @@
 
 from etna.datasets.tsdataset import TSDataset
 from etna.metrics import MAE
-from etna.models.nn.deepar import DeepARModel
-from etna.transforms.datetime_flags import DateFlagsTransform
-from etna.transforms.pytorch_forecasting import PytorchForecastingTransform
+from etna.models.nn import DeepARModel
+from etna.transforms import DateFlagsTransform
+from etna.transforms import PytorchForecastingTransform
 
 
 @pytest.mark.long

tests/test_models/nn/test_tft.py

@@ -6,9 +6,9 @@
 
 from etna.datasets.tsdataset import TSDataset
 from etna.metrics import MAE
-from etna.models.nn.tft import TFTModel
-from etna.transforms.datetime_flags import DateFlagsTransform
-from etna.transforms.pytorch_forecasting import PytorchForecastingTransform
+from etna.models.nn import TFTModel
+from etna.transforms import DateFlagsTransform
+from etna.transforms import PytorchForecastingTransform
 
 
 @pytest.mark.long