plugins: DiskIO UGens - include boost/atomic.hpp

Signed-off-by: Tim Blechmann <tim@klingt.org>
external libraries: boost.lockfree - msvc compile fix

Signed-off-by: Tim Blechmann <tim@klingt.org>
qtcollider: variable-sized arrays are not c++, we should use alloca instead

Signed-off-by: Tim Blechmann <tim@klingt.org>