Merge branch 'maint'

* maint: Amend git-push refspec documentation git-gc --prune is deprecated svn-git: Use binmode for reading/writing binary rev maps diff options documentation: refer to --diff-filter in --name-status Don't force imap.host to be set when imap.tunnel is set git-clone.txt: Adjust note to --shared for new pruning behavior of git-gc git-svn bug with blank commits and author file archive.c: format_subst - fixed bogus argument to memchr copy.c: copy_fd - correctly report write errors gitattributes: Fix subdirectory attributes specified from root directory