localrepo: move the changegroup method in changegroup module
This is a gratuitous code move aimed at reducing the localrepo bloatness.
The method had few callers, not enough to be kept in local repo.
The peer API stay unchanged.
localrepo: move the getbundle method in changegroup module
This is a gratuitous code move aimed at reducing the localrepo bloatness.
The method had few callers, not enough to be kept in local repo.
The peer API remains unchanged.