Dont try to load null streams as identities

Fises issue 3703

Change-Id: Ide3378913131062ddcb60dd6a0995b2383934990
Reviewed-on: http://gerrit.dmdirc.com/933
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>
Reviewed-by: Shane Mc Cormack <shane@dmdirc.com>

src/com/dmdirc/plugins/PluginInfo.java

@@ -309,6 +309,11 @@ public class PluginInfo implements Comparable<PluginInfo>, ServiceProvider {
                     continue;
                 }
 
+                if (stream == null) {
+                    //Don't add null streams
+                    continue;
+                }
+
                 try {
                     final Identity thisIdentity = new Identity(stream, false);
                     identities.add(thisIdentity);