Replace Registered Users with repo-discuss

Try to combat some of the change and voting spam by requiring membership
in the repo-discuss [1] group.

For Googlers to retain the current permissions assign the permissions to
mdb/all-users which is the group that represents all Googlers.

[1] https://groups.google.com/u/1/g/repo-discuss

Change-Id: Ic3fbaa7956755c3a236e489d4a89dede550a32d0

groups

diff --git a/groups b/groups
index 54bdb36..38fd73a 100644
--- a/groups
+++ b/groups
@@ -7,5 +7,6 @@
 global:Anonymous-Users                                        	Anonymous Users
 global:Change-Owner                                           	Change Owner
 global:Project-Owners                                         	Project Owners
-global:Registered-Users                                       	Registered Users
+google:AI2Pq9qu-dfHSnYQ5RUG4jxZsWaKNBQKqqkY27q3IzSe-gAFhSk-Y_8	google/repo-discuss@googlegroups.com
 google:AI2Pq9rwJtXWrKQ9Q62CcHSid7ngIF2hCfJ4bSpVquX_P2z5kFM6v9s	google/gerritcodereview-maintainers@googlegroups.com
+mdb:all-users                                                 	mdb/all-users

project.config

diff --git a/project.config b/project.config
index c3c7c7a..3dbee38 100644
--- a/project.config
+++ b/project.config
@@ -12,13 +12,17 @@
 	read = group Anonymous Users
 	owner = group google/gerritcodereview-maintainers@googlegroups.com
 [access "refs/for/refs/heads/*"]
-	push = group Registered Users
-	pushMerge = group Registered Users
+	push = group google/repo-discuss@googlegroups.com
+	push = group mdb/all-users
+	pushMerge = group google/repo-discuss@googlegroups.com
+	pushMerge = group mdb/all-users
 	viewPrivateChanges = group gerrit-ci
 [access "refs/heads/*"]
-	forgeAuthor = group Registered Users
+	forgeAuthor = group google/repo-discuss@googlegroups.com
+	forgeAuthor = group mdb/all-users
 	label-Code-Review = -2..+2 group Project Owners
-	label-Code-Review = -1..+1 group Registered Users
+	label-Code-Review = -1..+1 group google/repo-discuss@googlegroups.com
+	label-Code-Review = -1..+1 group mdb/all-users
 	label-Verified = -1..+1 group Diffy Cuckoo
 	label-Verified = -1..+1 group Project Owners
 	label-Verified = -1..+1 group gerrit-trusted-contributors
@@ -39,7 +43,8 @@
 	read = group google/gerritcodereview-maintainers@googlegroups.com
 	label-Code-Review = -2..+2 group Project Owners
 	label-Code-Review = -2..+2 group google/gerritcodereview-maintainers@googlegroups.com
-	label-Code-Review = -1..+1 group Registered Users
+	label-Code-Review = -1..+1 group google/repo-discuss@googlegroups.com
+	label-Code-Review = -1..+1 group mdb/all-users
 	label-Verified = -1..+1 group Project Owners
 	label-Verified = -1..+1 group google/gerritcodereview-maintainers@googlegroups.com
 	submit = group Project Owners