use seq_region_start/end instead of start/end in sub overlaps as the test...

use seq_region_start/end instead of start/end in sub  overlaps as the test should not be relative to the slices they are on

modules/Bio/EnsEMBL/Feature.pm

@@ -1350,7 +1350,7 @@ sub overlaps {
     return undef;
   }
   
-  return ($self->end >= $f->start and $self->start <= $f->end);
+  return ($self->seq_region_end >= $f->seq_region_start and $self->seq_region_start <= $f->seq_region_end);
 }