- allows starting new processes and controlling them remotely from the parent process
  - remote processes can run their own GUI, Qt signals can be connected between processes
    (in general this is not possible with the built-in multiprocessing module due to
    the use of fork() ).
  - Control works by a system of proxy-objects such that controlling a remote process
    looks almost exactly like working with local objects.
  - Uses sockets to communicate between processes (so in theory could be made to 
    work over a network), but also includes a mode that uses fork() to allow fast
    parallelization.
  - Wicked-easy inline parallelization by adding only one line of code to break up work between
    processes (requires fork; sorry windows users)

  - GUI interactive python prompt, useful in a variety of situations where
    python -i or ipython don't work very well. 
  - Command history (requires a little help finding storage for this)
  - Exception catching, allowing the user to inspect local variables 
    at any level within a stack trace (currently, this is done _without_
    blocking the application)

Added workaround for Qt crash-at-exit bug (make sure that all GraphicsItems live in a scene before exiting)

- Added workaround for Qt bug: https://bugreports.qt-project.org/browse/QTBUG-18616. (GraphicsItem.setParent needs to check for scene change first)
This _could_ cause other problems, but they will certainly be fewer than the existing problems.

- Fixed bugs with ViewBox linking to views which are subsequently deleted

   - fixed AxisItem sometimes drawing the same tick twice (sometimes with different text)
   - fixed handling of record arrays in setting ScatterPlotItem point data

metaarray updates:
  - better handling of HDF5 files
  - fixed some isinstance problems that appear during reloads

  - added workaround for Qt bug: https://bugreports.qt-project.org/browse/QTBUG-18616
  - allow pxMode argument in PlotDataItem.setData()

Added SRTTransform3D

(should be no major API changes here)

The values returned are more useful now, but this introduces a minor API change.

 - optional context menu for ImageItem
 - inverted y-axis in Canvas (+y now points upward)
 - extra __init__ arguments for Dock
 - Transform can be constructed from Matrix4x4
 - many others

 - generating arrow paths
 - solving 3d affine mapping matrix
 - solving 2d bilinear mapping matrix

removed stray print statement

MetaArray update - no longer subclass of ndarray

- Moved some functionality from UIGraphicsItem upstream to GraphicsItem

Everything appears wo be working as normal in Python2
Python3 is still only partially functional.

  - performance improvements
  - removed 'identical' argument; this is now handled automatically
  - some minor API changes to SpotItem