suppress warnings

[AmberSJones]

there are cases where warnings in model development, etc. need to be suppressed.

[tannerlex]

convergence warning is suppressed after PR #67

suppression is still needed for:
/home/tjones/.local/lib/python3.6/site-packages/tensorflow/python/framework/tensor_util.py:523: DeprecationWarning: tostring() is deprecated. Use tobytes() instead.
tensor_proto.tensor_content = nparray.tostring()
/home/tjones/.local/lib/python3.6/site-packages/tensorflow/python/framework/tensor_util.py:523: DeprecationWarning: tostring() is deprecated. Use tobytes() instead.
tensor_proto.tensor_content = nparray.tostring()

I tried suppression using warning around the tensorflow call in modeling_utilities.train_model:
warnings.filterwarnings('ignore', message='tostring() is deprecated')
es = tf.keras.callbacks.EarlyStopping(monitor=monitor, patience=patience, mode=mode)
warnings.filterwarnings('default')
but it didn't work

I also tried the same around the scipy call in anomaly_utilities.set_dynamic_threshold:
z = norm.ppf(1 - alpha / 2)
but it didn't work either