Add ssh command create-branch for creating branches

This command will allow users to create branches via ssh.

Feature: Issue 1156
Change-Id: I270df6bc3ed95581aa2fc6845c654f2d9a5c72b1

Documentation/cmd-create-branch.txt

@@ -0,0 +1,58 @@
+gerrit create-branch
+====================
+
+NAME
+----
+gerrit create-branch - Create a new branch
+
+SYNOPSIS
+--------
+--
+'ssh' -p <port> <host> 'gerrit create-branch'
+  <PROJECT>
+  <NAME>
+  <REVISION>
+--
+
+DESCRIPTION
+-----------
+Creates a new branch for a project.
+
+ACCESS
+------
+Caller should have link:access-control.html#category_create[Create Reference]
+permission on the project.
+
+Administrators do not automatically have permission to create branches. It must
+be granted via the Create Reference permission.
+
+SCRIPTING
+---------
+This command is intended to be used in scripts.
+
+OPTIONS
+-------
+<PROJECT>::
+    Required; name of the project.
+
+<NAME>::
+    Required; name of the branch to be created.
+
+<REVISION>::
+    Required; base revision of the new branch.
+
+EXAMPLES
+--------
+Create a new branch called 'newbranch' from the 'master' branch of
+the project 'myproject'.
+
+====
+    $ ssh -p 29418 review.example.com gerrit create-branch myproject newbranch master
+====
+
+GERRIT
+------
+Part of link:index.html[Gerrit Code Review]
+
+SEARCHBOX
+---------