GitRepository/get_remote_repos: return URLs, too

GitRepository/get_remote_repos: return URLs, too

In addition to the remote name, return remote URLs. Return value is now
a dict with remote name as the key and a list of URLs as the value. The
first value in the list is the effective fetch URL, the rest of the
values are push URLs.

NOTE! This patch is to be dropped, not going for upstream.

Signed-off-by: Markus Lehtonen <markus.lehtonen@linux.intel.com>