[darwin] change path ..xbmc-depends/toolchain -> ..xbmc-depends/buildtools-native
Merge pull request #2421 from anssih/fix/AE-periodsize

AE: More tweaks to ALSA period and buffer sizes

This fixes HD audio passthrough regressions.
pvr: do not buffer canpause/seek, the server may want to change this
Merge pull request #2437 from FernetMenta/canseek

pvr: do not buffer canpause/seek, the server may want to change this
depends: fixup paths after f32039928
Merge pull request #2433 from tru/zeroconf_memleak

[OSX] Fix minor memory leak in ZeroconfOSX.cpp
[osx/ios] - fix build with old darwin-depends by exporting YASM via config.site (should fix billy for osx)
depends: fix typo, don't create tool_dir
depends: Prepend -target to staging to avoid clashes with old deps

Also, fix a few missed ARCHS -> CURRENT_ARCH
depends: add setuptools for build-side python
depends: add distutilscross for building host python modules
depends: add PIL dependency
depends: add PIL dependency, but don't build by default yet
depends: use distribute rather than setuptools. Thanks ulion
depends: fix pil include path, it's not guarded from system libzip
depends: python: fix urllib on darwin
[AEChannelInfo][*REVIEW*] What's the purpose of this assert?
fix copy-constructor of Buffer, which fixes xbmcvfs.read() (fixes #14183)
[depends/libshairport] - add volume control and AudioOutput struct versioning
[airtunes] - add volume contro for airtunes using libshairport (same like we already do on windows using libshairplay)