Updated persistent_storage (markdown)

persistent_storage.md

@@ -50,6 +50,29 @@ The possible disk states are:
      ```
 - `active`: The plugin contains data written into it's cached location.
 
+
+The CLI tool has Persistent Storage enabled by default using the operational mode of `auto`.
+- You can optionally specify `--storage-mode` allowing you to change ths; possibilities are `auto` (default), `flush`, and `memory`.
+   - `auto`: This is the default option and pesistent storage is used when applicable (only the plugins that require it take advantage of local cache made available to them).
+   - `flush`: Similar to `auto` except that any changes made are immediately flushed to disk.  This mode creates a higher i/o but enforces the content on disk is the latest.
+   - `memory`: Effectively turns off Persistent storage.  No plugins are allowed to write to disk.  This is exactly the way Apprise was prior ro the Persistent Storage feature.
+
+### Storage Cleanup
+- To remove all accumulated persistent storage generated through the CLI tool, you can run the following:
+    ```bash
+    apprise storage clean
+    ```
+-  You can compliment this call by providing URL IDs  and/or `--tag` (or `-g`) values to focus on only cleaning specific persistently cached data. For example:
+    ```bash
+    # Assuming we want to target the URL ID of abc123xy
+    apprise storage clean abc123xy
+    ```
+   You can also clear cache based on tag references:
+
+    ```bash
+    # Assuming we want to target the URL(s) associated with the tag 'family'
+    apprise storage clean --tag family
+    ```
 ## Developer Usage
 
 When developing your plugin, you can access the persistent storage via `self.store`.  There are 2 main features: