Add support for setting stepheight for entities

src/script/common/c_content.cpp

@@ -188,6 +188,8 @@ void read_object_properties(lua_State *L, int index,
 	getboolfield(L, -1, "is_visible", prop->is_visible);
 	getboolfield(L, -1, "makes_footstep_sound", prop->makes_footstep_sound);
 	getfloatfield(L, -1, "automatic_rotate", prop->automatic_rotate);
+	getfloatfield(L, -1, "stepheight", prop->stepheight);
+	prop->stepheight*=BS;
 }
 
 /******************************************************************************/