* Add a comprehensive set of residue templates

This adds all RNA, DNA, and protein/peptide residues as defined in the PDB
chemical component database that are "linking" residues

* Add bond template and atom template property mapping to PDB/CIF parsing.

* Fix atom serialization and fix a (poorly written) test.

* Modernize some test stuff

* Make sure we bundle a relevant JSON file.

* Finish tests and fix remaining issues.

Should be good to go now!

* Oops - fix error after refactor.

* Add missing ccd.js file

* Update .gitignore