* extend the allowed valences of the alkali earths
make it possible to have preferred and arbitrary valence states (I thought this already worked)
* backup
* maybe needed
* copy in some swig3 files;
at this point the tests all work
* remove SWIG version lock
* changes in response to review
* Wrapper fixes: Tversky for De Morgan and java byte functions for ExplicitBitVect
* Wrapper fixes: Tversky for De Morgan and java byte functions for ExplicitBitVect