BGE: Remove KX_IPOActuator.

KX_IPOActuator is not used since 2.4.

This patch removes:
	- KX_IPOActuator.h/cpp;
	- Python doc;
	- Write of IPO actuator in write.c;
	- Allocation of IPOactuator in sca.c;
	- Conversion in KX_ConvertActuators.cpp;
	- Initialization of the python proxy in KX_PythonInitTypes.cpp;
	- Other minor remove in logic_windows.c and in KX_PythonInit.cpp.

Reviewers: sybren, campbellbarton

Reviewed By: campbellbarton

Subscribers: moguri

Differential Revision: https://developer.blender.org/D1603

source/gameengine/Ketsji/KX_PythonInit.cpp

@@ -98,7 +98,6 @@ extern "C" {
 #include "SCA_PythonKeyboard.h"
 #include "SCA_PythonMouse.h"
 #include "KX_ConstraintActuator.h"
-#include "KX_IpoActuator.h"
 #include "KX_SoundActuator.h"
 #include "KX_StateActuator.h"
 #include "BL_ActionActuator.h"