Remove conference-wide RTX/REMB/TCC/opus-red options. (#1423)

* feat: Make enableRemb signal client remb support.

* feat: Make enableTcc signal client tcc support.

* ref: Remove the enableOpusRed conference-wide option.

modules/xmpp/moderator.js

             value: Boolean(config.disableRtx)
         }).up();
 
-    if (config.enableTcc !== undefined) {
-        elem.c(
-                'property', {
-                    name: 'enableTcc',
-                    value: Boolean(config.enableTcc)
-                }).up();
-    }
-    if (config.enableRemb !== undefined) {
-        elem.c(
-                'property', {
-                    name: 'enableRemb',
-                    value: Boolean(config.enableRemb)
-                }).up();
-    }
-    if (config.enableOpusRed === true) {
-        elem.c(
-                'property', {
-                    name: 'enableOpusRed',
-                    value: true
-                }).up();
-    }
-
     if (config.audioPacketDelay !== undefined) {
         elem.c(
             'property', {

modules/xmpp/xmpp.js

             this.caps.addFeature('http://jitsi.org/opus-red');
         }
 
+        if (typeof this.options.enableRemb === 'undefined' || this.options.enableRemb) {
+            this.caps.addFeature('http://jitsi.org/remb');
+        }
+        if (typeof this.options.enableTcc === 'undefined' || this.options.enableTcc) {
+            this.caps.addFeature('http://jitsi.org/tcc');
+        }
+
         // this is dealt with by SDP O/A so we don't need to announce this
         // XEP-0293
         // this.caps.addFeature('urn:xmpp:jingle:apps:rtp:rtcp-fb:0');