Update docker and install docs

Author: BichengYing

docs/docker.rst

@@ -23,13 +23,13 @@ Downloading Docker Image From Docker Hub
 
 .. code-block:: bash
 
-    sudo docker pull bluefoglib/bluefog:gpu-0.2.1
+    sudo docker pull bluefoglib/bluefog:gpu-0.2.2
 
 2. Download docker image with only CPU support:
 
 .. code-block:: bash
 
-    sudo docker pull bluefoglib/bluefog:cpu-0.2.1
+    sudo docker pull bluefoglib/bluefog:cpu-0.2.2
 
 Building Your Own Docker Image
 ##############################
@@ -57,7 +57,7 @@ if you download the docker image from `Docker Hub <https://hub.docker.com/r/blue
 
 .. code-block:: bash
 
-    sudo docker run --privileged -it --gpus all --name bluefog_gpu_deploy --network=host -v /mnt/share/ssh:/root/.ssh bluefog_gpu:latest
+    sudo docker run --privileged -it --gpus all --name bluefog_gpu_deploy --shm-size=64g --network=host -v /mnt/share/ssh:/root/.ssh bluefog_gpu:latest
 
 2. Run docker container with only CPU support:
 
@@ -114,4 +114,4 @@ The docker images have already included a few examples for the Bluefog library a
 
 .. code-block:: bash
 
-    bfrun -np 4 python examples/pytorch_average_consensus.py
+    bfrun -np 4 python examples/pytorch_mnist.py

docs/install.rst

@@ -22,6 +22,12 @@ After you think the environment is all set, just run following command to instal
 
     pip install --no-cache-dir bluefog
 
+.. Note::
+
+    We haven't fully tested our compatiblity with hisotrical torch versions.
+    It is guaranteed at least for ``torch==1.4.0`` and ``torchvision==0.5.0`` case.
+    Remember if the torch version is changed, you have to re-install bluefog completely.
+
 .. Note::
 
     If ``--no-cache-dir`` is not present, you may receive the error information like
@@ -80,13 +86,13 @@ For more details, check :ref:`Docker Usage` page.
 
 .. code-block:: bash
 
-    sudo docker pull bluefoglib/bluefog:gpu
+    sudo docker pull bluefoglib/bluefog:gpu-0.2.2
 
 2. Download docker image with only CPU support:
 
 .. code-block:: bash
 
-    sudo docker pull bluefoglib/bluefog:cpu
+    sudo docker pull bluefoglib/bluefog:cpu-0.2.2
 
 .. _conda: https://docs.conda.io/projects/conda/en/latest/user-guide/tasks/manage-environments.html
 .. _download link: https://www.open-mpi.org/software/ompi/v4.0/