[Kst-plot/kst] c67153: Add a pykst command: update_parent()

[Barth Netterfield]

  Branch: refs/heads/master
  Home:   https://github.com/Kst-plot/kst
  Commit: c671530dc7880c776a49d1162688a5d5be0ecca3
      https://github.com/Kst-plot/kst/commit/c671530dc7880c776a49d1162688a5d5be0ecca3
  Author: Barth Netterfield <netterfield at astro.utoronto.ca>
  Date:   2016-08-27 (Sat, 27 Aug 2016)

  Changed paths:
    M pyKst/demo/plot_layout.py
    M pyKst/demo/viewitems.py
    M pyKst/pykst.py
    M src/libkstapp/plotrenderitem.h
    M src/libkstapp/viewitem.h
    M src/libkstapp/viewitemscriptinterface.cpp

  Log Message:
  -----------
  Add a pykst command: update_parent()