Eliminated all "using" statements.  Get fixed width integer types from standard library (instead of boost).
Reset device in nidaq::Device destructor.  nidaq::Task and subclasses are now private to nidaq::Device.
Simplified implementation of nidaq::Task and subclasses
Cosmetic fixes
nidaq::Device::DigitalOutputTask now supports only a single channel per instance
nidaq::Task and subclasses are now public (again) with private constructors
Added task management to nidaq::Device
Updated nidaqtest as required by nidaqapi changes
Added support for clearing existing channels to nidaq::Device
Updated helper as required by nidaqapi changes
Removed nidaqpluginhelper-Prefix.pch.  Minor tweaks to Xcode project file.
Multiple digital output channels are now handled correctly.  Updated NIDAQDevice as required by helper changes.  Fixed some helper bugs.