Various Additions to the Documentation (#4139)

* Various docs improvements

* Update python/packages/autogen-core/docs/src/user-guide/core-user-guide/framework/command-line-code-executors.ipynb

---------

Co-authored-by: Eric Zhu <ekzhu@users.noreply.github.com>

python/packages/autogen-core/docs/src/user-guide/core-user-guide/framework/command-line-code-executors.ipynb

@@ -7,7 +7,7 @@
     "# Command Line Code Executors\n",
     "\n",
     "Command line code execution is the simplest form of code execution.\n",
-    "Generally speaking, it will save each code block to a file and the execute that file.\n",
+    "Generally speaking, it will save each code block to a file and then execute that file.\n",
     "This means that each code block is executed in a new process. There are two forms of this executor:\n",
     "\n",
     "- Docker ({py:class}`~autogen_ext.code_executor.docker_executor.DockerCommandLineCodeExecutor`) - this is where all commands are executed in a Docker container\n",
@@ -15,6 +15,11 @@
     "\n",
     "## Docker\n",
     "\n",
+    "```{note}\n",
+    "To use `DockerCommandLineCodeExecutor`, ensure the `autogen-ext[docker]` package is installed. For more details, see the [Packages Documentation](https://microsoft.github.io/autogen/dev/packages/index.html).\n",
+    "\n",
+    "```\n",
+    "\n",
     "The {py:class}`~autogen_ext.code_executor.docker_executor.DockerCommandLineCodeExecutor` will create a Docker container and run all commands within that container. \n",
     "The default image that is used is `python:3-slim`, this can be customized by passing the `image` parameter to the constructor. \n",
     "If the image is not found locally then the class will try to pull it. \n",