The non-NT portion has been moved to wpiutil.
The NT portion has been moved to ntcore (as NTSendable).
SendableBuilder similarly split and moved.
SendableRegistry moved to wpiutil.
In C++, SendableHelper also moved to wpiutil.
This enables use of Sendable from wpimath and also enables
moving several classes from wpilib to wpimath.
This removes the name and subsystem from individual objects, and instead
puts this data into a new singleton class, SendableRegistry. Much of
LiveWindow has been refactored into SendableRegistry.
In C++, a new CRTP helper class, SendableHelper, has been added to provide
move and destruction functionality.
Shims for GetName, SetName, GetSubsystem, and SetSubsystem have been added
to Command and Subsystem (both old and new), and also to SendableHelper to
prevent code breakage.
This deprecates SendableBase in preparation for future removal.
A templated hal::Handle class is used to wrap handles to make them move-only.
This eliminates a lot of boilerplate move constructor/assignment code
in the main WPILib classes. HAL_SPIPort and HAL_I2CPort are also wrapped.
The wrapper class does not implement destruction. This would require the
wrapper class to be handle-specific (rather than generic) and would result
in more code added than it removed, plus would add header dependencies on
more HAL headers. In addition, some HAL handle release functions are more
complex (e.g. have return values) and can't be easily mapped to a destructor.
The old headers were moved into folders because doing so avoids polluting
the system include directories.
Folder names were also normalized to lowercase.
