superproject: Display status messages during repo init/sync.

Superproject objects accept the optional argument “quiet”.
The following progress messages are displayed if quiet is false.

Displayed the following message whenever we find we have to make a new
folder (aka new remote), because if you started with repo init android
and later do googleplex-android that is when it will be slow.

"<location>: Performing initial setup for superproject; this might take
several minutes.".

After fetch completion, added the following notification:
"<location>: Initial setup for superproject completed."

Tested the code with the following commands.

$ ./run_tests -v

Tested the sync code by using repo_dev alias and pointing to this CL.

$ repo_dev init -u persistent-https://googleplex-android.git.corp.google.com/platform/manifest -b rvc-dev  --partial-clone --clone-filter=blob:limit=10M --repo-rev=main  --use-superproject

Bug: [google internal] b/181178282
Bug: https://crbug.com/gerrit/13707
Change-Id: Ia7fb85c6fb934faaa90c48fc0c55e7f41055f48a
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/299122
Reviewed-by: Mike Frysinger <vapier@google.com>
Tested-by: Raman Tenneti <rtenneti@google.com>

subcmds/sync.py

@@ -292,7 +292,8 @@ later is required to fix a server side protocol bug.
       Returns path to the overriding manifest file.
     """
     superproject = git_superproject.Superproject(self.manifest,
-                                                 self.repodir)
+                                                 self.repodir,
+                                                 quiet=opt.quiet)
     all_projects = self.GetProjects(args,
                                     missing_ok=True,
                                     submodules_ok=opt.fetch_submodules)