How to build a new plugin:
1. Start xcode, create a new "Carbon bundle" project
2. Create the project under building/macosNNproc/variant/MyPlugin
   e.g.  building/macos32x86/squeak.cog.v3/MyPlugin
3. Edit the project settings:
   Header Search Path: /Developer/Headers/FlatCarbon
4. Add the following files:
   ../../../../src/v3.cog/interp.h
   ../../../../platforms/Cross/vm/sqMemoryAccess.h
   ../../../../platforms/Cross/vm/sqVirtualMachine.h
   ../../../../platforms/Mac OS/vm/config.h
   ../../../../platforms/Mac OS/vm/sqConfig.h
   ../../../../platforms/Mac OS/vm/sqPlatformSpecific.h
5. Add the files for your plugin from
   ../../../../platforms/Cross/MyPlugin
   ../../../../platforms/Mac OS/MyPlugin
   ../../../../src/plugins/MyPlugin
6. Cross your fingers and compile

Alternatively, adapt the Template provided here. Be sure to edit VMSRCDIR to be
the directory containing interp.h from the VM you're adding the plugin to.
