Rename the xmpp-parsers directory to parsers

This doesn’t change anything to the name of the crate, just makes
autocompletion easier by not sharing the same prefix as the xmpp crate.

xmpp-parsers/src/jingle_rtcp_fb.rs

@@ -1,47 +0,0 @@
-// Copyright (c) 2019 Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this
-// file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
-generate_element!(
-    /// Wrapper element for a rtcp-fb.
-    RtcpFb, "rtcp-fb", JINGLE_RTCP_FB,
-    attributes: [
-        /// Type of this rtcp-fb.
-        type_: Required<String> = "type",
-
-        /// Subtype of this rtcp-fb, if relevant.
-        subtype: Option<String> = "subtype",
-    ]
-);
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use crate::Element;
-    use std::convert::TryFrom;
-
-    #[cfg(target_pointer_width = "32")]
-    #[test]
-    fn test_size() {
-        assert_size!(RtcpFb, 24);
-    }
-
-    #[cfg(target_pointer_width = "64")]
-    #[test]
-    fn test_size() {
-        assert_size!(RtcpFb, 48);
-    }
-
-    #[test]
-    fn parse_simple() {
-        let elem: Element =
-            "<rtcp-fb xmlns='urn:xmpp:jingle:apps:rtp:rtcp-fb:0' type='nack' subtype='sli'/>"
-                .parse()
-                .unwrap();
-        let rtcp_fb = RtcpFb::try_from(elem).unwrap();
-        assert_eq!(rtcp_fb.type_, "nack");
-        assert_eq!(rtcp_fb.subtype.unwrap(), "sli");
-    }
-}