docs fix

HACKING.md

@@ -67,7 +67,7 @@ terminus-pluginname
 
 # Plugins
 
-The app will load all plugins from the source checkout in the dev mode, and from the user's plugins directory at all times (click `Open Plugins Directory` under `Settings` > `Plugins`).
+The app will load all plugins from the source checkout in the dev mode, from the user's plugins directory at all times (click `Open Plugins Directory` under `Settings` > `Plugins`) and from the directory specified by the `TERMINUS_PLUGINS` environment var.
 
 A plugin should only provide a default export, which should be a `NgModule` class (or a `NgModuleWithDependencies` where applicable). This module will be injected as a dependency to the app's root module.
 

README.md

@@ -25,4 +25,4 @@
 
 Pull requests and plugins are welcome! Publish your plugin on NPM with a `terminus-plugin` keyword to make them appear in the Plugin Manager.
 
-See [HACKING.md](https://github.com/Eugeny/terminus/blob/master/HACKING.md) for a very plugin development tutorial!
+See [HACKING.md](https://github.com/Eugeny/terminus/blob/master/HACKING.md) for a very brief plugin development tutorial!