Don't bump alignment for small structures on x64 to stay compatible with ABI.
Update OSX runtime build to use embedded clang from Unity repo.
Unbreak iphone simulator build.
do not try to find manage frames when stepping out from either, last managed frame or frame in between managed/native ones (fix case #573949)
Merge pull request #129 from Unity-Technologies/unity-4.5-staging

merging, as jonathan approved the changes over skype