Update docs

Author: aclark4life

Diff for: docs/source/installation/usage.rst

@@ -0,0 +1,16 @@
+Usage
+=====
+
+.. code:: bash
+
+    $ dm --help
+    Usage: dm [OPTIONS] COMMAND [ARGS]...
+
+      Django MongoDB CLI
+
+    Options:
+      --help  Show this message and exit.
+
+    Commands:
+      repo          Run Django fork and third-party library tests.
+      startproject  Run `startproject` with custom templates.

Diff for: docs/source/installation/venv.rst

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+Create a virtual environment
+============================
+
+::
+
+    python -m venv .venv
+    source .venv/bin/activate