Rewording and add plugin page to the index

Author: joelwurtz

plugins/always-seekable-body-plugin.rst

@@ -1,8 +1,8 @@
 Always Seekable Body Plugin
 ===========================
 
-The ``AlwaysSeekableBodyPlugin`` ensure that body of the request and body of the response are always seekable.
-This allows a lot of components that read the stream to rewind it in order to be used later by another component::
+``AlwaysSeekableBodyPlugin`` ensure that the body used in request and response is always seekable.
+This allows a lot of components, reading the stream, to rewind it in order to be used later by another component::
 
     use Http\Discovery\HttpClientDiscovery;
     use Http\Client\Common\PluginClient;
@@ -19,7 +19,7 @@ This allows a lot of components that read the stream to rewind it in order to be
         [$alwaysSeekableBodyPlugin]
     );
 
-The plugin supports the following options:
+This plugin supports the following options (which are passed to the ``BufferedStream`` class):
 
  * ``use_file_buffer``: Whether it should use a temporary file to buffer the body of a stream if it's too big
  * ``memory_buffer_size``: Maximum memory to use for buffering the stream before it switch to a file

plugins/index.rst

@@ -10,6 +10,7 @@ request or you can even start a completely new request. This gives you full cont
 
    introduction
    build-your-own
+   always-seekable-body-plugin
    authentication
    cache
    content-length