option to build the BGE without python, uses existing python check (cmake and scons)

when python is disabled videotextures are not built.

source/gameengine/Ketsji/BL_Shader.cpp

@@ -728,6 +728,8 @@ void BL_Shader::SetUniform(int uniform, const int* val, int len)
 	}
 }
 
+#ifndef DISABLE_PYTHON
+
 PyMethodDef BL_Shader::Methods[] = 
 {
 	// creation
@@ -1409,4 +1411,6 @@ KX_PYMETHODDEF_DOC( BL_Shader, setUniformDef, "setUniformDef(name, enum)" )
 	return NULL;
 }
 
+#endif // DISABLE_PYTHON
+
 // eof