cmd/gitmirror: fix html in handleRoot
cmd/gitmirror: fix html in handleRoot

Change-Id: Ie0ab89caedae20dbb8c38cba1f872a7539fb48f8
Reviewed-on: https://go-review.googlesource.com/121437
Reviewed-by: Brad Fitzpatrick <ae9783c0b0efc69cd85ab025ddd17aa44cdc4aa5@golang.org>

golang/build,golang/build,golang/build,golang/build