git-codereview: add mail --no-verify option

This adds a flag to set git push --no-verify, disabling pre-push hooks.

Change-Id: I9ef686bd3ec742901d0138fc9028d65efde83e87
Reviewed-on: https://go-review.googlesource.com/c/review/+/222922
Trust: Damien Neil <dneil@google.com>
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Trust: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/git-codereview/mail.go b/git-codereview/mail.go
index 2e6c6a6..44d83d6 100644
--- a/git-codereview/mail.go
+++ b/git-codereview/mail.go
@@ -27,6 +27,7 @@
 		trust       = flags.Bool("trust", false, "add a Trust+1 vote to the CL")
 		trybot      = flags.Bool("trybot", false, "run trybots on the uploaded CLs")
 		wip         = flags.Bool("wip", false, "set the status of a change to Work-in-Progress")
+		noverify    = flags.Bool("no-verify", false, "disable presubmits")
 	)
 	flags.Var(rList, "r", "comma-separated list of reviewers")
 	flags.Var(ccList, "cc", "comma-separated list of people to CC:")
@@ -155,6 +156,9 @@
 	if *noKeyCheck {
 		args = append(args, "-o", "nokeycheck")
 	}
+	if *noverify {
+		args = append(args, "--no-verify")
+	}
 	args = append(args, "origin", refSpec)
 	run("git", args...)