updated docs on 'path' config option

README.md

@@ -181,7 +181,7 @@ Each filter that you specify have the following options:
 
  - `type` - determine the type of filter to be used, refer to *Filters* section for more information
  - `options` - options that should be passed to the specific filter type
- - `path` - override the global `cache_prefix` and replace it with this path
+ - `path` - used in place of the filter name to determine the path in combination with the global `cache_prefix`
  - `quality` - override the default quality of 100 for the generated images
 
 ## Built-in Filters