[RCD] Top-posting and signature below the quote

According to short discussion in http://trac.roundcube.net/ticket/1489001 I see that it is possible to set top-posting with signature below the quote. It sounds confusing and useless.

Now when we have "When replying" option (reply_mode) I propose to remove "When replying or forwarding place signature" option (sig_above). Signature position should be always below the reply text (not the quote) and reply_mode already defines this position.

reply_mode=0 -> reply below the quote with sig below the reply text reply_mode=1 -> reply above the quote with sig below the reply text

Any objections?