This works similarly to how our shell stores its settings from a software design standpoint.
- Add settings.cpp file and ShellSettings structure to load and save settings.
- Add a registry value to hivedef.inf for the locked toolbar state.
This prevents a bug where the associated registry key cannot be opened or saved to.
- Add new BWM_SETTINGCHANGE window message to refresh the UI on setting changes
and send it to every open window when saving settings to the registry.
- Add new BWM_GETSETTINGSPTR window message to share the shellbrowser settings
structure pointer with child windows and toolbars.
