[ci skip] clarify phases in docker-options plugin

docs/docker-options.md

@@ -14,7 +14,7 @@ $ dokku help
 ...
 ````
 
-Add some options
+Add some options (first, for the deployed/running app and second when executing `dokku run`)
 
 ```bash
 $ dokku docker-options:add myapp deploy "-v /host/path:/container/path"
@@ -25,9 +25,9 @@ Check what we added
 
 ```bash
 $ dokku docker-options myapp
-Run options:
+Deploy options:
-    --link container_name:alias
     -v /host/path:/container/path
+Run options:
     -v /another/container/path
 ```
 
@@ -36,10 +36,18 @@ Remove an option
 $ dokku docker-options:remove myapp run "--link container_name:alias"
 ```
 
+Note about `dokku` phases and `docker-options`
+------------
+`dokku` deploys your application in multiple "phases" and the `docker-options` plugin allows you to pass arguments to the underlying docker container in the following 3 phases/containers
+- `build`: the container that executes the appropriate buildpack
+- `deploy`: the container that executes your running/deployed application
+- `run`: the container that executes any arbitrary command via `dokku run myapp`
+
+
 Advanced Usage (avoid if possible)
 ------------
 
-In your applications folder (/home/dokku/app_name) create a file called DOCKER_OPTIONS_RUN (or DOCKER_OPTIONS_BUILD or DOCKER_OPTIONS_DEPLOY).
+In your applications folder (`/home/dokku/app_name`) create a file called `DOCKER_OPTIONS_RUN` (or `DOCKER_OPTIONS_BUILD` or `DOCKER_OPTIONS_DEPLOY`).
 
 Inside this file list one docker option per line. For example:
 
@@ -49,7 +57,7 @@ Inside this file list one docker option per line. For example:
 -v /another/container/path
 ```
 
-The above example will result in the following options being passed to docker during docker run:
+The above example will result in the following options being passed to docker during `dokku run`:
 
 ```bash
 --link container_name:alias -v /host/path:/container/path -v /another/container/path