[Bf-python] info on PyDict_SetItemString()

[Ken Hughes]

A heads-up for those who didn't know it (including me, until about 10 
minutes ago):

PyDict_SetItemString() [ and probably PyDict_SetItem() ] make a new 
reference to the value inserted into the dictionary, so make sure you 
Py_DECREF() the object afterward if necessary.  I've found a number of 
places where we're not doing so (and plan to go through tonight an 
tomorrow to correct if possible).

Ken