[19.03 backport] assorted docs and completion script fixes

contrib/completion/zsh/_docker

@@ -9,6 +9,7 @@
 #   - Felix Riedel
 #   - Steve Durrheimer
 #   - Vincent Bernat
+#   - Rohan Verma
 #
 # license:
 #
@@ -2784,7 +2785,7 @@ __docker_subcommand() {
                 $opts_help \
                 "($help -p --password)"{-p=,--password=}"[Password]:password: " \
                 "($help)--password-stdin[Read password from stdin]" \
-                "($help -u --user)"{-u=,--user=}"[Username]:username: " \
+                "($help -u --username)"{-u=,--username=}"[Username]:username: " \
                 "($help -)1:server: " && ret=0
             ;;
         (logout)

docs/reference/commandline/events.md

@@ -31,7 +31,12 @@ Options:
 ## Description
 
 Use `docker events` to get real-time events from the server. These events differ
-per Docker object type.
+per Docker object type. Different event types have different scopes. Local 
+scoped events are only seen on the node they take place on, and swarm scoped 
+events are seen on all managers.
+
+Only the last 1000 log events are returned. You can use filters to further limit 
+the number of events returned.
 
 ### Object types
 
@@ -160,6 +165,9 @@ that have elapsed since January 1, 1970 (midnight UTC/GMT), not counting leap
 seconds (aka Unix epoch or Unix time), and the optional .nanoseconds field is a
 fraction of a second no more than nine digits long.
 
+Only the last 1000 log events are returned. You can use filters to further limit 
+the number of events returned.
+
 #### Filtering
 
 The filtering flag (`-f` or `--filter`) format is of "key=value". If you would

docs/reference/commandline/run.md

@@ -605,6 +605,33 @@ PS C:\> docker run --device=class/86E0D1E0-8089-11D0-9CE4-08003E301F73 mcr.micro
 > Windows containers. This option fails if the container isolation is `hyperv`
 > or when running Linux Containers on Windows (LCOW).
 
+### Access an NVIDIA GPU
+
+The `--gpus­` flag allows you to access NVIDIA GPU resources. First you need to
+install [nvidia-container-runtime](https://nvidia.github.io/nvidia-container-runtime/).
+Visit [Specify a container's resources](https://docs.docker.com/config/containers/resource_constraints/)
+for more information.
+
+To use `--gpus`, specify which GPUs (or all) to use. If no value is provied, all
+available GPUs are used. The example below exposes all available GPUs.
+
+```bash
+$ docker run -it --rm --gpus all ubuntu nvidia-smi
+```
+
+Use the `device` option to specify GPUs. The example below exposes a specific
+GPU.
+
+```bash
+$ docker run -it --rm --gpus device=GPU-3a23c669-1f69-c64e-cf85-44e9b07e7a2a ubuntu nvidia-smi
+```
+
+The example below exposes the first and third GPUs.
+
+```bash
+$ docker run -it --rm --gpus device=0,2 nvidia-smi
+```
+
 ### Restart policies (--restart)
 
 Use Docker's `--restart` to specify a container's *restart policy*. A restart