Merge branch 'br/imap-send-simplify-tunnel-child-process'

Code clean-up. * br/imap-send-simplify-tunnel-child-process: imap-send: simplify v_issue_imap_cmd() and get_cmd_result() using starts_with() imap-send.c: imap_folder -> imap_server_conf.folder git-imap-send: simplify tunnel construction