[MINOR] Add description of POST /batches
## What changes were proposed in this pull request?
Just added a description of POST /batches in the api-doc.
## How was this patch tested?
Since the change is quite small, I didn't test the patch. If I have an instruction, I will follow it.
Author: Shingo Furuyama <sfuruyam@yahoo-corp.jp>
Closes #283 from marblejenka/add-description.
diff --git a/docs/rest-api.md b/docs/rest-api.md
index f1ff9b4..cca937f 100644
--- a/docs/rest-api.md
+++ b/docs/rest-api.md
@@ -389,6 +389,8 @@
### POST /batches
+Creates a new batch session.
+
#### Request Body
<table class="table">
