WIP: Upgrade oscpack to 1.1.0

This is for issue #1911.

I tried to modify oscpack as little as possible to make future upgrades as smooth as possible. 
So far I only changed the filenames in ip/win32. 
I guess we _still_ need the respective ifdefs like before, for the IDE projects which don't use make, @arturoc?

those files are excluded with a pattern in `addon_config.mk` on makefile-enabled platforms, does this work the way I did @bakercp @arturoc? (i.e. exclude in common, re-include on windows platforms?) It would be nice because then you only have specify two platform sections.

The [osx Nil fix](1d1ed0f306dfb68d28575bad6de0741350034fd5) is apparently handled within oscpack now, so no modifications for that necessary.

The [host endianness detection](https://github.com/openframeworks/openFrameworks/commit/8ecd5aa758a62e3221f580e307fd267fa65f87a1#diff-2) should also [be fixed within oscpack now](https://code.google.com/p/oscpack/source/detail?r=87#), but would probably good to try.

The reused ports and broadcasting functionality are [included in oscpack now](https://code.google.com/p/oscpack/source/detail?r=86) (and off by default). I have wrapped those in private functions (if wanted we can make those public), and added optional parameters to the relevant constructors. I have chosen to leave both off by default, since all the implications are not really clear, and people who need this can now easily enable it.

Open question:
* I'm not sure why https://code.google.com/p/oscpack/source/detail?spec=svn86&r=70 doesn't have more impact, i.e. compile warnings? I'm compiling on 64bit currently, maybe that is masking it?
* Does the `addon_config.mk` work the way I did it?
* Do we still need the platform ifdefs around the win/posix IP implementation?

So far it looks good (the OscChatSystemExample works flawlessly), although I can't test cross-platform and windows IDEs. Would appreciate feedback on the implementation and thorough testing, as I only have a quite superficial understanding of the ofxOsc implementation intricacies.
@kylemcdonald @ofTheo @arturoc @damiannz