second half of fixing mod manager

[ab9rf]

this adds an implementation of lua_insert2 for the stl_container_identity template, overriding the base class container_identity version of this method

the change to add-spatter's link libraries is due to add-spatter using an interpose; with this change plugins that use interposes must link Lua libraries due to header entanglement. while this is suboptimal, untangling the headers to avoid this is going to be a good deal of work and would delay this hotfix, so....