Use fast enumeration rather than NSEnumerator
Add stricter flags for warnings and errors for compilation. Fixed some issues with the C++ classes.

NOTE! I'm no C++ developer. I hope I've fixed those issues correctly. If I haven't submit patches please.
Start transition to ARC.
- Enable ARC.
- Disable ARC for specific files with issues.
Update WAN2Device for ARC. Remove unnecessary code, ivars, declarations.
Convert a whole bunch of files to ARC. Change a lot of code formatting. (incomplete)
ARCify the rest of the library. Change more formatting. Correct the handling of protocols vs classes/objects for observers.
Drop support for Xcode 3
Create a convenience header file
Update the demo project.
Include the upnpx project in the demo project so it builds the static library.
Change demo project to not use deprecated methods.
Remove unnecessary boilerplate code.