Merge branch 'hv/fetch-moved-submodules-on-demand'

"git fetch --recurse-submodules" now knows that submodules can be moved around in the superproject in addition to getting updated, and finds the ones that need to be fetched accordingly. * hv/fetch-moved-submodules-on-demand: submodule: simplify decision tree whether to or not to fetch implement fetching of moved submodules fetch: add test to make sure we stay backwards compatible