smartlog: handle upstreams properly
smartlog: handle upstreams properly

When a local branch 'A' has another local branch 'B' as an upstream, 'smartlog'
is incorrectly omitting the commits from branch 'B'.  To fix this,
remove other local branches from the @upstreams array, which is
subsequently used as an omit list.

bmwill/dotfiles,bmwill/dotfiles