Added existing property-path for tljh-config set method

docs/topic/tljh-config.rst

@@ -47,6 +47,59 @@ do so with the following:
 
 This can only set string and numerical properties, not lists.
 
+Some of the existing ``<property-path>`` are listed below by categories:
+
+**Authentication**
+
+    Use ``auth.type`` to determine authenticator to use. All parameters
+    in the config under ``auth.{auth.type}`` will be passed straight to the
+    authenticators themselves.
+
+**User Lists**
+
+* ``users.allowed`` takes in usernames to whitelist
+
+* ``users.banned`` takes in usernames to blacklist
+
+* ``users.admin`` takes in usernames to designate as admins
+
+**User Server Limits**
+
+* ``limits.memory`` Specifies the maximum memory that can be used by each
+  individual user. It can be specified as an absolute byte value. You can use
+  the suffixes K, M, G or T to mean Kilobyte, Megabyte, Gigabyte or Terabyte
+  respectively. Setting it to ``None`` disables memory limits.
+
+  .. code-block:: bash
+
+     sudo tljh-config set limits.memory 4G
+
+  Even if you want individual users to use as much memory as possible,
+  it is still good practice to set a memory limit of 80-90% of total
+  physical memory. This prevents one user from being able to single
+  handedly take down the machine accidentally by OOMing it.
+
+* ``limits.cpu`` A float representing the total CPU-cores each user can use.
+  1 represents one full CPU, 4 represents 4 full CPUs, 0.5 represents
+  half of one CPU, etc. This value is ultimately converted to a percentage and
+  rounded down to the nearest integer percentage,
+  i.e. 1.5 is converted to 150%, 0.125 is converted to 12%, etc.
+  Setting it to ``None`` disables CPU limits.
+
+  .. code-block:: bash
+
+     sudo tljh-config set limits.cpu 2
+
+**User Environment**
+
+    ``user_environment.default_app`` Set default application users are
+    launched into. Currently can be set to the following values
+    ``jupyterlab`` or ``nteract``
+
+    .. code-block:: bash
+
+       sudo tljh-config set user_environment.default_app jupyterlab
+
 View current configuration
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