Made both equals() methods null safe

modules/Bio/EnsEMBL/Feature.pm

@@ -435,6 +435,9 @@ sub equals {
   if ( $self eq $feature ) {
     return 1;
   }
+  if ( ! defined $feature ) {
+    return 0;
+  }
 
   assert_ref( $feature, 'Bio::EnsEMBL::Feature' );
 

modules/Bio/EnsEMBL/Transcript.pm

@@ -2092,6 +2092,7 @@ sub equals {
   my ( $self, $transcript ) = @_;
 
   if ( $self eq $transcript ) { return 1 }
+  if ( ! defined $transcript ) { return 0 }
 
   assert_ref( $transcript, 'Bio::EnsEMBL::Transcript' );