make email column in users model optional. #196
add custom hash to as response. #198
simplify authentication. #198
added modified omniauth-orcid gem. #196
allow ORCID admin users to add email address #196
added ENV variables for authentication
release documentation and version bump
remove unused username attribute. #198
added sciencetoolbox import filter. #199
more flexible import options. #191
handle nil dates on import. #191
add indexes for works identifier columns. #130
fine-tuning of csl import. #191
small tweaks to import subclasses. #191
updated release notes