Add --all-reviewers to ssh gerrit-query

The new allReviewers parameter allows users to view the name and
email of all reviewers which are added to a change (irrespective of
whether they have been voting on that change or not).

Feature: Issue 2102
Change-Id: I655a49c37b959eb2f0bb705e2c45cb9bdc33ea23
diff --git a/Documentation/json.txt b/Documentation/json.txt
index 2836e5b..9278cde 100644
--- a/Documentation/json.txt
+++ b/Documentation/json.txt
@@ -72,6 +72,9 @@
 submitRecords:: The <<submitRecord,submitRecord attribute>> contains
 information about whether this change has been or can be submitted.
 
+allReviewers:: List of all reviewers in <<account,account attribute>>
+which are added to a change.
+
 [[trackingid]]
 trackingid
 ----------