docs: Document author and committer log parameters

Format the +log api documentation to make it more readable.

Issue: 376381593
Change-Id: Ia96889d6a16fc88eb27758b4e4915890cf6e9adb

Documentation/api-reference.md

diff --git a/Documentation/api-reference.md b/Documentation/api-reference.md
index 5f0ae79..837712e 100644
--- a/Documentation/api-reference.md
+++ b/Documentation/api-reference.md
@@ -25,12 +25,19 @@
 `https://gerrit.googlesource.com/a/gitiles/+log/refs/heads/master?n=10&format=JSON`
 
 Shows the commit log.
-Use the parameter `n=<number>` to limit the number of commits returned.
-For paging use the start parameter `s=<next_cursor>`.
-Use the parameter `grep=<pattern>` to filter commits by commit message.
-The `next` key in the JSON provides a cursor for the next page. Use it with `s=<next_cursor>`.
-The final page will have no `next` key.
-Every page except for the first will have a `previous` cursor to page backwards.
+
+##### Filter parameters
+* `author=<name or email>`
+* `committer=<name or email>`
+* `grep=<pattern>`
+
+#### Limit and Paging parameters
+* `n=<number>` to limit the number of commits returned.
+* `s=<start_number>` to set start during paging.
+   The `next` key in the JSON response provides a cursor for the next page.
+   Use it with `s=<next_cursor>`.
+   The final page will have no `next` key.
+   Every page except for the first will have a `previous` cursor to page backwards.
 
 #### **`+show`**
 `https://gerrit.googlesource.com/a/gitiles/+show/refs/heads/master/?format=JSON`