capture: Implement per-stream volume control for capture streams.

This piggy backs onto the previous changes for protocol 22 and
thus does not bump the version. This and the previous commits should be
seen as mostly atomic. Apologies for any bisecting issues this causes
(although I would expect these to be minimal)

src/pulsecore/cli-command.c

@@ -632,7 +632,7 @@ static int pa_cli_command_source_volume(pa_core *c, pa_tokenizer *t, pa_strbuf *
     }
 
     pa_cvolume_set(&cvolume, 1, volume);
-    pa_source_set_volume(source, &cvolume, TRUE);
+    pa_source_set_volume(source, &cvolume, TRUE, TRUE);
     return 0;
 }