If we are going to read the refspecs in a batch, we can use `git_remote_get_fetch_refspecs` and `git_remote_get_pull_refspecs`, with return an array. However, it is a string array, not an array of `refspec` handles, so we can not use the the `refspec_*` methods. Shall we parse the refspecs in libgit2sharp to create the `RefSpec` objects? (also see my comment on the pull request below)