* include/aclui.h: Replace __OBJC__ guard with _OBJC_NO_COM.
* include/basetyps.h: Likewise.
(_COM_interface): New define.
(interface): Define to _COM_interface, conditional on !__OBJC__.
Replace 'interface' with '_COM_interface', throughout.
* include/comcat.h: Replace 'interface' with '_COM_interface', throughout.
* include/commdlg.h: Replace __OBJC__ guard with _OBJC_NO_COM.
* include/docobj.h: Replace 'interface' with '_COM_interface', throughout.
* include/mshtml.h: Likewise.
* include/oaidl.h: Likewise.
* include/objfwd.h: Likewise.
* include/objidl.h: Likewise.
* include/ocidl.h: Likwise.
* include/olectl.h: Likewise.
* include/oleidl.h: Likewise.
* include/shlobj.h: Likewise.
* include/shlwapi.h: Replace __OBJC__ guard with _OBJC_NO_COM.
* include/vfw.h: Likewise.
* include/windows.h. Likewise. Add comment.
* include/directx/d3d9.h: Replace 'interface' with '_COM_interface',
throughout.
* lib/test.c: Replace __OBJC__ guard with _OBJC_NO_COM.
Add test for conflict with '@interface'