Fix remnants of is_mod->is_module rename
Fix remnants of is_mod->is_module rename

Fixed both `Module#instance_methods` and `Module#to_s`

kachick/opal,iliabylich/opal,kachick/opal,opal/opal,jgaskins/opal,opal/opal,Mogztter/opal,Mogztter/opal,iliabylich/opal,kachick/opal,opal/opal,jgaskins/opal,wied03/opal,jgaskins/opal,wied03/opal,opal/opal,wied03/opal,Mogztter/opal,kachick/opal,iliabylich/opal,Mogztter/opal