Fix OSX division-by-zero in ViewBox
Fixed unicode issues with PySide loadUiType
Added unit test for loadUiType
Start stability tests:
 - randomly add / remove widgets and graphicsitems to provoke a crash
 - create and delete various objects and ensure that nothing is left in memory
stability test is successfully crashing, ref_cycle test exposes cycles!
Fixed ref cycle in SignalProxy
update stability test
Expanded ref checks
Fixed ref cycle in ImageItem -> HistogramLutItem
Expand ref cycle check to include all child QObjects
Add GraphicsWindow ref check
disabled stability test (because it is expected to crash)
Merge branch 'stability_tests' into develop
Added code for inverting X axis
Update AxisItem.setGrid docstring
docstring indentation fix
Updated ImageView and ViewBox documentation
Fix: TextParameterItem now obeys 'readonly' option
Fixed Parameter 'readonly' option for bool, color, and text parameter types
Initialize drag variable in Dock.py
Added Dock close button (from Stefan H)
minor cleanups