cleanup of imports
New commit of structure/codec package
Merge branch 'master' of github.com:pwrose/symmetry
Added RcsbPdbInMemoryDatabase
Merge branch 'master' of github.com:pwrose/symmetry
resolving merge conflict
Misc. changes
Checkin new unit tests

Checkin new unit tests
Added InMemoryDB code
Adding dependency in Structure Codec
Merge branch 'master' of github.com:rcsb/symmetry