Support function to rename symbols on RenameClass command

Now `rename_class` method doesn't support to replace symbols (e.g. global var, type glob, and etc), so implemented it.
How do you feel?

## SYNOPSIS
    $Foo::Bar::GLOBAL_VAR
     ~~~~~~~~ Rename here

    $Foo::Bar::Buz::GLOBAL_VAR # <= Don't rename
               ~~~ cuz here name space exists, so both are different