[update of SandwichFeatures]
- table name change ( sw_by_components -> sandwich)
- generate resfile for more general case also (before this, it supports for poor seq_rec case for RelaxDesign only)
- finished refactoring in accordance of better naming convention (use 'using
namespace' inside of specific strand_assembly namespace)
- should not change any integration tests other than (expected) features and features_database_schema
- I think that there is no need to ask 'pull request' since I think
that I am the only one who uses SandwichFeatures as of now