Allow gerrit-verifiers to edit topic on changes

Currently only change and project owners may edit a topic.

Widen the permission to include gerrit-verifiers, which is
a manually curated group of known and trusted contributors.

Force permission (i.e. changing the topic on merged changes)
is omitted and thus limited to project owners.

Change-Id: I47fa2a3ae02e9535478111a0bfba26d4388b98a2

groups

diff --git a/groups b/groups
index 53c050d..5613c45 100644
--- a/groups
+++ b/groups
@@ -1,5 +1,6 @@
 # UUID                                                        	Group Name
 #
+b49f61711e6c0148f9f4d90702015bb894289be9                      	gerrit-verifiers
 e076e6ae9e389d476b0dcf1427cca2dcda4f77c6                      	Diffy Cuckoo
 global:Anonymous-Users                                        	Anonymous Users
 global:Project-Owners                                         	Project Owners

project.config

diff --git a/project.config b/project.config
index c957b87..4159353 100644
--- a/project.config
+++ b/project.config
@@ -22,6 +22,7 @@
 	label-Verified = -1..+1 group Project Owners
 	submit = group Project Owners
 	editTopicName = +force group Project Owners
+	editTopicName = group gerrit-verifiers
 [access "refs/meta/config"]
 	push = group Project Owners
 	push = group google/gerritcodereview-maintainers@googlegroups.com