Load debug.so extensions along with the debug gem itself

- This doesn't work still, but now for new reasons.

```
     NoMethodError:
       undefined method `b' for #<Binding:0x0000000107a7e088>

             binding.b
                    ^^
     # ./test/migrator_spec.rb:72:in `block (3 levels) in <top (required)>'
```

and if I add `require "debug"` to the spec_helper again it gives:

```
LoadError:
  cannot load such file -- debug
```

but, doing a `require "debug"; binding.b` in `migrator_spec` _does_ work.

Where is the require coming from where it works some of the time but not through all of the layers we have?

Library/Homebrew/standalone/init.rb

@@ -40,9 +40,11 @@
 end
 
 if Pathname.new(RbConfig.ruby).to_s.include?("/vendor/portable-ruby/")
- prefix = RbConfig::CONFIG["rubylibprefix"]
  ruby_version = RbConfig::CONFIG["ruby_version"]
- $LOAD_PATH.unshift "#{prefix}/gems/#{ruby_version}/gems/debug-1.6.3/lib"
+ ruby_path = "#{RbConfig::CONFIG["rubylibprefix"]}/gems/#{ruby_version}"
+
+ $LOAD_PATH.unshift "#{ruby_path}/extensions/#{Gem::Platform.local}/#{ruby_version}-static/debug-1.6.3"
+ $LOAD_PATH.unshift "#{ruby_path}/gems/debug-1.6.3/lib"
 end
 
 unless $LOAD_PATH.include?(HOMEBREW_LIBRARY_PATH.to_s)